实验三

#include<stdio.h>
int main()
{
    long int x,y,t,i;
    i = 1;
    y = 0;
    printf("Enter a number: ");
    scanf("%ld",&x);
    while(x != 0)
    {
        t = x % 10;
        x = x / 10;
        if (t % 2 !=0)
        {
            y = y + t * i;
            i = i * 10;
        }
    }

    printf("new number is %ld", y);

    return 0;
}

#include<stdio.h>
#include<math.h>
int main()
{
    int i, n, m;
    n = 101;
    m = 0;
    while (n > 100 && n < 200)
    {
        for (i = 2; i < sqrt((double)n); i++)
        {
            if (n % i == 0)
                break;
        }
        if (i >= sqrt((double)n))
        {
            m++;
            printf("%6d",n);
            if (m % 5 == 0)
                printf("\n");
        }
        n++;
    }
    printf("\n");
    printf("101~200之间共有%d个素数",m);
        return 0;
}

#include<stdio.h>
#include<stdlib.h>
int main()
{
    int number, max, min, n;

    n = 1;
    printf("输入第%d个数：", n);
    scanf("%d", &number);
    max = number;
    min = number;

    while (n>0&&n<5)
    {
        n++;
        printf("输入第%d个数：",n);
        scanf("%d", &number);

        if (number>max)
            max = number;
        else if (number<min)
            min = number;
    }

    printf("最大数为：%d\n", max);
    printf("最小数为：%d\n", min);

    return 0;
}