RosettaCodeData/Task/Four-is-magic/C/four-is-magic.c
2023-07-01 13:44:08 -04:00

98 lines
2.7 KiB
C

#include <stdint.h>
#include <stdio.h>
#include <glib.h>
typedef struct named_number_tag {
const char* name;
uint64_t number;
} named_number;
const named_number named_numbers[] = {
{ "hundred", 100 },
{ "thousand", 1000 },
{ "million", 1000000 },
{ "billion", 1000000000 },
{ "trillion", 1000000000000 },
{ "quadrillion", 1000000000000000ULL },
{ "quintillion", 1000000000000000000ULL }
};
const named_number* get_named_number(uint64_t n) {
const size_t names_len = sizeof(named_numbers)/sizeof(named_number);
for (size_t i = 0; i + 1 < names_len; ++i) {
if (n < named_numbers[i + 1].number)
return &named_numbers[i];
}
return &named_numbers[names_len - 1];
}
size_t append_number_name(GString* str, uint64_t n) {
static const char* small[] = {
"zero", "one", "two", "three", "four", "five", "six", "seven", "eight",
"nine", "ten", "eleven", "twelve", "thirteen", "fourteen", "fifteen",
"sixteen", "seventeen", "eighteen", "nineteen"
};
static const char* tens[] = {
"twenty", "thirty", "forty", "fifty", "sixty", "seventy", "eighty", "ninety"
};
size_t len = str->len;
if (n < 20) {
g_string_append(str, small[n]);
}
else if (n < 100) {
g_string_append(str, tens[n/10 - 2]);
if (n % 10 != 0) {
g_string_append_c(str, '-');
g_string_append(str, small[n % 10]);
}
} else {
const named_number* num = get_named_number(n);
uint64_t p = num->number;
append_number_name(str, n/p);
g_string_append_c(str, ' ');
g_string_append(str, num->name);
if (n % p != 0) {
g_string_append_c(str, ' ');
append_number_name(str, n % p);
}
}
return str->len - len;
}
GString* magic(uint64_t n) {
GString* str = g_string_new(NULL);
for (unsigned int i = 0; ; ++i) {
size_t count = append_number_name(str, n);
if (i == 0)
str->str[0] = g_ascii_toupper(str->str[0]);
if (n == 4) {
g_string_append(str, " is magic.");
break;
}
g_string_append(str, " is ");
append_number_name(str, count);
g_string_append(str, ", ");
n = count;
}
return str;
}
void test_magic(uint64_t n) {
GString* str = magic(n);
printf("%s\n", str->str);
g_string_free(str, TRUE);
}
int main() {
test_magic(5);
test_magic(13);
test_magic(78);
test_magic(797);
test_magic(2739);
test_magic(4000);
test_magic(7893);
test_magic(93497412);
test_magic(2673497412U);
test_magic(10344658531277200972ULL);
return 0;
}