实验一

#include <stdio.h>
int main()
{
    int x;
    printf("输入一个整数：\n");
    scanf("%d",&x);
    if(x%2==1)
    printf("是奇数");
    else
    printf("是偶数");
    return 0;
 } 

#include <stdio.h>
int main()
{
    int days;
    printf("输入一个整数：\n");
    scanf("%d",&days);
    if(days>=1&&days<=5)
    printf("workdays,fghting\n");
    else if(days==7||days==6)
    printf("weekdays,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(ch>='a'&&ch<='z')
    printf("%c\n",ch-'a'+'A');
    else
    printf("%c\n",ch);
    return 0;
 }