判断整数的位数

#include<stdio.h>

int main(void)
{
    int x;
    int n = 0;
    
    scanf_s("%d", &x);

    x = x / 10;
    n++;

    while (x > 0)
    {
        x = x / 10;
        n++;
    }

    printf("%d
", n);

    return 0;
}

#include<stdio.h>

int main(void)
{
    int x;
    int n = 0;

    scanf_s("%d", &x);

    do
    {
        x = x / 10;
        n++;
    } while (x > 0);

    printf("%d
", n);

    return 0;
}

#include<stdio.h>

int main(void)
{
    int x, y =1;
    int n = 0;

    scanf_s("%d", &x);

    do
    {
        x = x / 10;
        n++;
    } while (x != 0);    //不等于0，继续循环

    printf("%d
", n);

    return 0;
}