draft

programs/p412/info.json

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+{
+  "language": "C",
+  "name": "演習 4-12",
+  "description": "入力した正の整数値の桁数を表示するプログラム。",
+  "output": {
+    "type": "screenshot",
+    "content": "./assets/p412.png"
+  },
+  "note": ""
+}

programs/p412/main.c

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+#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;
+}