Data update
This commit is contained in:
Ingy döt Net
parent
5150844a7d
commit
4bb20c9b71
7735 changed files with 38060 additions and 199180 deletions
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@ -2,7 +2,7 @@
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@interface HuffmanTree : NSObject {
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int freq;
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int freq;
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}
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-(instancetype)initWithFreq:(int)f;
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@property (nonatomic, readonly) int freq;
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@ -11,34 +11,34 @@
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@implementation HuffmanTree
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@synthesize freq; // the frequency of this tree
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-(instancetype)initWithFreq:(int)f {
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if (self = [super init]) {
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freq = f;
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}
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return self;
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if (self = [super init]) {
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freq = f;
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}
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return self;
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}
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@end
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const void *HuffmanRetain(CFAllocatorRef allocator, const void *ptr) {
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return (__bridge_retained const void *)(__bridge id)ptr;
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return (__bridge_retained const void *)(__bridge id)ptr;
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}
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void HuffmanRelease(CFAllocatorRef allocator, const void *ptr) {
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(void)(__bridge_transfer id)ptr;
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(void)(__bridge_transfer id)ptr;
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}
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CFComparisonResult HuffmanCompare(const void *ptr1, const void *ptr2, void *unused) {
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int f1 = ((__bridge HuffmanTree *)ptr1).freq;
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int f2 = ((__bridge HuffmanTree *)ptr2).freq;
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if (f1 == f2)
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return kCFCompareEqualTo;
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else if (f1 > f2)
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return kCFCompareGreaterThan;
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else
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return kCFCompareLessThan;
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int f1 = ((__bridge HuffmanTree *)ptr1).freq;
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int f2 = ((__bridge HuffmanTree *)ptr2).freq;
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if (f1 == f2)
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return kCFCompareEqualTo;
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else if (f1 > f2)
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return kCFCompareGreaterThan;
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else
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return kCFCompareLessThan;
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}
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@interface HuffmanLeaf : HuffmanTree {
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char value; // the character this leaf represents
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char value; // the character this leaf represents
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}
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@property (readonly) char value;
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-(instancetype)initWithFreq:(int)f character:(char)c;
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@ -47,16 +47,16 @@ CFComparisonResult HuffmanCompare(const void *ptr1, const void *ptr2, void *unus
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@implementation HuffmanLeaf
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@synthesize value;
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-(instancetype)initWithFreq:(int)f character:(char)c {
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if (self = [super initWithFreq:f]) {
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value = c;
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}
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return self;
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if (self = [super initWithFreq:f]) {
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value = c;
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}
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return self;
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}
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@end
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@interface HuffmanNode : HuffmanTree {
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HuffmanTree *left, *right; // subtrees
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HuffmanTree *left, *right; // subtrees
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}
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@property (readonly) HuffmanTree *left, *right;
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-(instancetype)initWithLeft:(HuffmanTree *)l right:(HuffmanTree *)r;
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@ -65,86 +65,86 @@ CFComparisonResult HuffmanCompare(const void *ptr1, const void *ptr2, void *unus
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@implementation HuffmanNode
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@synthesize left, right;
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-(instancetype)initWithLeft:(HuffmanTree *)l right:(HuffmanTree *)r {
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if (self = [super initWithFreq:l.freq+r.freq]) {
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left = l;
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right = r;
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}
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return self;
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if (self = [super initWithFreq:l.freq+r.freq]) {
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left = l;
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right = r;
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}
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return self;
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}
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@end
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HuffmanTree *buildTree(NSCountedSet *chars) {
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CFBinaryHeapCallBacks callBacks = {0, HuffmanRetain, HuffmanRelease, NULL, HuffmanCompare};
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CFBinaryHeapRef trees = CFBinaryHeapCreate(NULL, 0, &callBacks, NULL);
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// initially, we have a forest of leaves
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// one for each non-empty character
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for (NSNumber *ch in chars) {
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int freq = [chars countForObject:ch];
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if (freq > 0)
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CFBinaryHeapAddValue(trees, (__bridge const void *)[[HuffmanLeaf alloc] initWithFreq:freq character:(char)[ch intValue]]);
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}
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NSCAssert(CFBinaryHeapGetCount(trees) > 0, @"String must have at least one character");
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// loop until there is only one tree left
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while (CFBinaryHeapGetCount(trees) > 1) {
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// two trees with least frequency
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HuffmanTree *a = (__bridge HuffmanTree *)CFBinaryHeapGetMinimum(trees);
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CFBinaryHeapRemoveMinimumValue(trees);
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HuffmanTree *b = (__bridge HuffmanTree *)CFBinaryHeapGetMinimum(trees);
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CFBinaryHeapRemoveMinimumValue(trees);
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// put into new node and re-insert into queue
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CFBinaryHeapAddValue(trees, (__bridge const void *)[[HuffmanNode alloc] initWithLeft:a right:b]);
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}
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HuffmanTree *result = (__bridge HuffmanTree *)CFBinaryHeapGetMinimum(trees);
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CFRelease(trees);
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return result;
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CFBinaryHeapCallBacks callBacks = {0, HuffmanRetain, HuffmanRelease, NULL, HuffmanCompare};
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CFBinaryHeapRef trees = CFBinaryHeapCreate(NULL, 0, &callBacks, NULL);
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// initially, we have a forest of leaves
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// one for each non-empty character
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for (NSNumber *ch in chars) {
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int freq = [chars countForObject:ch];
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if (freq > 0)
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CFBinaryHeapAddValue(trees, (__bridge const void *)[[HuffmanLeaf alloc] initWithFreq:freq character:(char)[ch intValue]]);
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}
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NSCAssert(CFBinaryHeapGetCount(trees) > 0, @"String must have at least one character");
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// loop until there is only one tree left
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while (CFBinaryHeapGetCount(trees) > 1) {
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// two trees with least frequency
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HuffmanTree *a = (__bridge HuffmanTree *)CFBinaryHeapGetMinimum(trees);
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CFBinaryHeapRemoveMinimumValue(trees);
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HuffmanTree *b = (__bridge HuffmanTree *)CFBinaryHeapGetMinimum(trees);
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CFBinaryHeapRemoveMinimumValue(trees);
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// put into new node and re-insert into queue
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CFBinaryHeapAddValue(trees, (__bridge const void *)[[HuffmanNode alloc] initWithLeft:a right:b]);
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}
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HuffmanTree *result = (__bridge HuffmanTree *)CFBinaryHeapGetMinimum(trees);
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CFRelease(trees);
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return result;
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}
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void printCodes(HuffmanTree *tree, NSMutableString *prefix) {
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NSCAssert(tree != nil, @"tree must not be nil");
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if ([tree isKindOfClass:[HuffmanLeaf class]]) {
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HuffmanLeaf *leaf = (HuffmanLeaf *)tree;
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// print out character, frequency, and code for this leaf (which is just the prefix)
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NSLog(@"%c\t%d\t%@", leaf.value, leaf.freq, prefix);
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} else if ([tree isKindOfClass:[HuffmanNode class]]) {
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HuffmanNode *node = (HuffmanNode *)tree;
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// traverse left
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[prefix appendString:@"0"];
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printCodes(node.left, prefix);
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[prefix deleteCharactersInRange:NSMakeRange([prefix length]-1, 1)];
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// traverse right
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[prefix appendString:@"1"];
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printCodes(node.right, prefix);
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[prefix deleteCharactersInRange:NSMakeRange([prefix length]-1, 1)];
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}
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NSCAssert(tree != nil, @"tree must not be nil");
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if ([tree isKindOfClass:[HuffmanLeaf class]]) {
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HuffmanLeaf *leaf = (HuffmanLeaf *)tree;
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// print out character, frequency, and code for this leaf (which is just the prefix)
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NSLog(@"%c\t%d\t%@", leaf.value, leaf.freq, prefix);
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} else if ([tree isKindOfClass:[HuffmanNode class]]) {
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HuffmanNode *node = (HuffmanNode *)tree;
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// traverse left
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[prefix appendString:@"0"];
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printCodes(node.left, prefix);
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[prefix deleteCharactersInRange:NSMakeRange([prefix length]-1, 1)];
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// traverse right
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[prefix appendString:@"1"];
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printCodes(node.right, prefix);
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[prefix deleteCharactersInRange:NSMakeRange([prefix length]-1, 1)];
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}
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}
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int main(int argc, const char * argv[]) {
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@autoreleasepool {
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NSString *test = @"this is an example for huffman encoding";
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// read each character and record the frequencies
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NSCountedSet *chars = [[NSCountedSet alloc] init];
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int n = [test length];
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for (int i = 0; i < n; i++)
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[chars addObject:@([test characterAtIndex:i])];
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// build tree
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HuffmanTree *tree = buildTree(chars);
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// print out results
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NSLog(@"SYMBOL\tWEIGHT\tHUFFMAN CODE");
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printCodes(tree, [NSMutableString string]);
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NSString *test = @"this is an example for huffman encoding";
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// read each character and record the frequencies
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NSCountedSet *chars = [[NSCountedSet alloc] init];
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int n = [test length];
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for (int i = 0; i < n; i++)
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[chars addObject:@([test characterAtIndex:i])];
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// build tree
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HuffmanTree *tree = buildTree(chars);
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// print out results
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NSLog(@"SYMBOL\tWEIGHT\tHUFFMAN CODE");
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printCodes(tree, [NSMutableString string]);
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}
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return 0;
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}
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