实验3

#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>=1&&n<=4) {
        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);
    
    system("pause");
    
    return 0;
} 

#include<stdio.h>
#include<math.h> 
int isprime(int n);
int main()
{
    int i;
    int s;
    s=0;  
    for(i=101;i<=200;i++)
    {
        if(isprime(i))
        {
            s++;
            printf("%5d",i);  
        }
    }
    printf("\n") ;
    printf("101~200之间共有%d个素数",s);
    return 0; 
}
int isprime(int n)
{
    int k;
    for(k=2;k<=sqrt(n);k++)
    if(n%k==0)
    return 0;
    return 1;
}

#include<stdio.h> 
int main(){
    long int s,a=1,b=0;
printf("请输入一个数字:\n");
    scanf("%ld",&s);
    while(s)
    {
        if((s%10)%2==1)
        {
            b=b+(s%10)*a;
            a=a*10;
        }
        s=s/10;
    }
    printf("新数字是:%ld\n",b);
    return 0;
}

#include<stdio.h>
int main(){
    int n,a,i;
    double s,m;
    m=0;s=0;i=1;
    printf("请输入n和a:");
    scanf("%d%d",&n,&a);
    while(i<=n)
    {
        m=m*10+a;
        s=s+i/m;
        i++;
    }
    printf("s=%lf",s);
    return 0;
}