实验三

#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<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);
    
    system("pause");
    
    return 0;
} 

#include<stdio.h>
#include<math.h>
int isprime(int n);
int main()
{
    int i,j=0;
    for(i=101;i<=200;i++)
    {
        if(isprime(i))
        {
            
             printf("%4d",i);
            j++;
            if(j%5==0)
            printf("\n");
        }
        else
        j=j+0;
    }
    printf("\n""101~200之间共有%d个素数",j);
    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 s;
    printf("Enter a number:");
    int m,n,i;
    n=0,i=1;
    scanf("%ld",&s);
    while(s>0)
    {
        m=s%10;
        s=s/10;
        if(m%2!=0)
        {
            n=n+m*i;
            i=i*10;
        }
        else
        n=n+0;
    }
    
    printf("new number is:%d",n);
    return 0;
    
}

#include<stdio.h>
int main()
{
    int n,a;
    float i,j,m,s;
    j=1,m=0,s=0;
    printf("Enter n and a:");
    scanf("%d%d",&n,&a);
        for(i=1;i<=n;i++)
        {
            m=m+a*j;
            j=j*10;
            s=s+i/m;
        }
        printf("s=%lf",s);
        return 0;
    }