draft

programs/p412/main.c

@@ -0,0 +1,24 @@
+#include <stdio.h>
+
+int main(void) {
+    int n;
+
+    do {
+        printf("Input positive integer: ");
+        scanf("%d", &n);
+        if (n <= 0) {
+            puts("\aPlease input non-negative, non-zero integer.");
+        }
+    } while (n <= 0);
+
+    int d = 0;
+    int x = n;
+    while (x > 0) {
+        x /= 10;
+        d++;
+    }
+
+    printf("%d is %d digit number.\n", n, d);
+
+    return 0;
+}