实验一

#include <stdio.h>  
int main() 
{    
int x;        
printf("输入一个整数: \n");   
scanf("%d",&x);       
  if( x%2==0)        printf("是偶数");  
    else        printf("是奇数");      
       return 0; 
        }

#include <stdio.h>
  int main() {
      int days;
             printf("输入一个整数: \n");
                 scanf("%d",&days);
                      // 补足×××处的表达式，使得满足程序功能描述
                          if(1<=days&&days<=5)
                              printf("workdays, fighting\n");
                                  else if(6<=days&&days<=7)
                                          printf("weekend, relax~\n");
                                              else        printf("Ooops, not in 1~7\n");
                                                      return 0; 
                                                       } 

#include <stdio.h> 
int main() {    
char ch;        
printf("输入一个字符:\n");    
scanf("%c",&ch);   
if(97<=ch&&ch<=122)  
ch=ch-32;
printf("%c\n",ch);        
return 0;  
}