Day1

day1/elves.c

@@ -0,0 +1,49 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define BUFFER_SIZE 32
+#define TOP_ELVES   3
+
+unsigned n, sum = 0U, max[TOP_ELVES];
+
+void update_maxs(unsigned long in) {
+    for (int i = 0; i < TOP_ELVES; i++) {
+        if (in > max[i]) {
+            for (int j = TOP_ELVES - 1; j > i; j--) {
+                max[j] = max[j-1];
+            }
+            max[i] = in;
+            break;
+        }
+    }
+}
+
+int main() {
+    memset(max, 0, TOP_ELVES*sizeof(unsigned));
+
+    char *buf, *p, c;
+    buf = (char *)malloc(BUFFER_SIZE);
+    memset(buf, 0, BUFFER_SIZE);
+    p = buf;
+
+    while ((c = getchar()) != EOF) {
+        *p++ = c;
+        if (c == '\n') {
+            if (buf[0] == '\n') {
+                update_maxs(sum); 
+                sum = 0;
+            } else {
+                sscanf(buf, "%u", &n);
+                sum += n;
+            }
+            memset(buf, 0, BUFFER_SIZE);
+            p = buf;
+        }
+    }
+
+    free(buf);
+    for (int i = 0; i < TOP_ELVES; i++) {
+        printf("%i. %u\n", i+1, max[i]);
+    }
+}