C语言前期算法整理

1. 分别获得一个四位数的个、十、百、千位上的数字

#include <stdio.h>
 
int main(void)
{
    int num = 1234;
    int ge = 0;
    int shi = 0;
    int bai = 0;
    int qian = 0;

    ge = num % 10;
    shi = num / 10 % 10;
    bai = num / 100 % 10;
    qian = num / 1000;

    printf("ge = %d\n", ge);
    printf("shi = %d\n", shi);
    printf("bai = %d\n", bai);
    printf("qian = %d\n", qian);

    return 0;
}

2. 判断闰年

#include <stdio.h>

int main(void)
{
    int year = 0;

    scanf("%d", &year);

    if (0 == year % 4 && 0 != year % 100 || 0 == year % 400)
    {
        printf("leapyear!\n");
    }else 
    {
        printf("not leapyear!\n");
    }

    return 0;
}

3. 打印水仙花数

#include <stdio.h>

int main(void)
{
    int num = 0;
    int ge = 0;
    int shi = 0;
    int bai = 0;

    for (num = 100; num < 1000; num++)
    {
        ge = num % 10;
        shi = num / 10 % 10;
        bai = num / 100;

        if (ge * ge * ge + shi * shi * shi + bai * bai * bai == num)
        {
            printf("%d\n", num);
        }
    }

    return 0;
}