修改文件结构。

POP/05/Optional03.c

@@ -0,0 +1,17 @@
+#include <stdio.h>
+
+int main() {
+    int N = 0, count[3] = {0};
+    // Count[0] stores the number of occerence of 5, [1] counts for 6, [2] counts for 7
+    scanf("%d", &N);
+    while (N > 0) {
+        switch (N % 10) {
+            case 5: count[0]++; break;
+            case 6: count[1]++; break;
+            case 7: count[2]++; break;
+        }
+        N /= 10;
+    }
+    printf("%d %d %d", count[0], count[1], count[2]);
+    return 0;
+}