第九次作业

#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>
#include<stdlib.h>
main(){
        double sum1=0,sum2=0,sum;
        int i;
        for(i=1;i<=100;i++)
        {
                 if(i%2==1)
                         sum1=sum1+1.0/i;
                 else sum2=sum2-1.0/i;
}
sum=sum1+sum2;
printf("%f\n",sum);
system("pause");
return 0;
}

 

 

#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);
}