第八次作业

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

main(){
    int x,guess;
    srand((unsigned int)time(NULL));
    guess=rand()%100;
    while(1){
        printf("请输入数字\n");
        scanf("%d",&x);
        if(x>guess){
            printf("高了\n");
        }
        else if(x<guess){
            printf("低了\n");
        }
        else{
            printf("猜对了\n");
            break;
        }
    }
}

 

 

#include<stdio.h>
main()
{
    int i,k=1;
    float sum=0;
    for(i=1;i<=100;i++)
    {
        sum+=k*1.0/i;k=-k;
    }
     printf("sum=%f\n",sum);
}

 

 

#include<stdio.h>
main(){
   int i,n,sum=0,result=0;
   printf("input n:\n");
   scanf("%d",&n);
   for(i=1;i<=n;i++){
       sum+=i;
       result+=sum;
   }
   printf("s=%d",result);

}

 

 

#include<stdio.h>
main(){
    long x;
    int temp=0,num=0;
    printf("请输入一个整数:\n");
    scanf("%ld",&x);
    printf("它的每一位数字是:\n");
    while(x>0)
    {
        printf("%3d",x%10);
        temp=temp*10+x%10;
        x=x/10;
        num++;
    }
    printf("\n它是一个%d位数.\n",num);
    printf("它的逆序是:%d\n",temp);
}