[C Examples] 입력된 숫자의 각 자리수를 더하고 3과 9로 나누어지는지 살펴보는 예제코드: do while(), if()

입력된 숫자의 각 자리수를 더하고 3과 9로 나누어지는지 살펴보는 예제코드: do while(), if()

포스트 난이도: HOO_Junior

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# Example Codes

 

#include <stdio.h>

int main() {
    int num, digit, sum=0;
    printf("Enter a positive integer: ");
    scanf("%d", &num);

    do {
        digit = num % 10;
        sum += digit;
        num /= 10;
    } while (num != 0);

    printf("The sum of the digits = %d\n", sum);

    num = sum;
    do {
        num -= 3;
    } while (num >= 3);
    if (num == 0) {
        printf("%d is divisible by 3\n", sum);
    } else {
        printf("%d is not divisible by 3\n", sum);
    }

    num = sum;
    do {
        num -= 9;
    } while (num >= 9);
    if (num == 0) {
        printf("%d is divisible by 9\n", sum);
    } else {
        printf("%d is not divisible by 9\n", sum);
    }

    return 0;
}

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# Results

 

Enter a positive integer: 66
The sum of the digits = 12
12 is divisible by 3
12 is not divisible by 9

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Enter a positive integer: 150
The sum of the digits = 6
6 is divisible by 3
6 is not divisible by 9

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