Data commit

Task/Knapsack-problem-0-1/C/knapsack-problem-0-1.c

@@ -0,0 +1,78 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef struct {
+    char *name;
+    int weight;
+    int value;
+} item_t;
+
+item_t items[] = {
+    {"map",                      9,   150},
+    {"compass",                 13,    35},
+    {"water",                  153,   200},
+    {"sandwich",                50,   160},
+    {"glucose",                 15,    60},
+    {"tin",                     68,    45},
+    {"banana",                  27,    60},
+    {"apple",                   39,    40},
+    {"cheese",                  23,    30},
+    {"beer",                    52,    10},
+    {"suntan cream",            11,    70},
+    {"camera",                  32,    30},
+    {"T-shirt",                 24,    15},
+    {"trousers",                48,    10},
+    {"umbrella",                73,    40},
+    {"waterproof trousers",     42,    70},
+    {"waterproof overclothes",  43,    75},
+    {"note-case",               22,    80},
+    {"sunglasses",               7,    20},
+    {"towel",                   18,    12},
+    {"socks",                    4,    50},
+    {"book",                    30,    10},
+};
+
+int *knapsack (item_t *items, int n, int w) {
+    int i, j, a, b, *mm, **m, *s;
+    mm = calloc((n + 1) * (w + 1), sizeof (int));
+    m = malloc((n + 1) * sizeof (int *));
+    m[0] = mm;
+    for (i = 1; i <= n; i++) {
+        m[i] = &mm[i * (w + 1)];
+        for (j = 0; j <= w; j++) {
+            if (items[i - 1].weight > j) {
+                m[i][j] = m[i - 1][j];
+            }
+            else {
+                a = m[i - 1][j];
+                b = m[i - 1][j - items[i - 1].weight] + items[i - 1].value;
+                m[i][j] = a > b ? a : b;
+            }
+        }
+    }
+    s = calloc(n, sizeof (int));
+    for (i = n, j = w; i > 0; i--) {
+        if (m[i][j] > m[i - 1][j]) {
+            s[i - 1] = 1;
+            j -= items[i - 1].weight;
+        }
+    }
+    free(mm);
+    free(m);
+    return s;
+}
+
+int main () {
+    int i, n, tw = 0, tv = 0, *s;
+    n = sizeof (items) / sizeof (item_t);
+    s = knapsack(items, n, 400);
+    for (i = 0; i < n; i++) {
+        if (s[i]) {
+            printf("%-22s %5d %5d\n", items[i].name, items[i].weight, items[i].value);
+            tw += items[i].weight;
+            tv += items[i].value;
+        }
+    }
+    printf("%-22s %5d %5d\n", "totals:", tw, tv);
+    return 0;
+}