实验1C语言开发环境使用和数据类型、运算符、表达式

# include 
int main() 
{
char ch;
printf("输入一个字符:\n");
scanf("%c",&ch);
if(ch>='a'&&ch<='z') 
ch=ch-'a'+'A'; 
printf("%c\n",ch);
return 0;
}

 

 

#include 
int main() {
int days;
printf("输入一个整数: \n");
scanf("%d",&days);

if(days>=1&&days<=5) 
printf("workdays, fighting\n");
else if(days==6||days==7) 
printf("weekend, relax~\n");
else
printf("Ooops, not in 1~7\n");
return 0;
}

 

 

 

 

 

 

 

//关系运算和逻辑运算
# include
int main()
{
    int a=5,b=8,c=8;
    printf("%d,%d,%d,%d\n",a==b&&a==c,a!=b&&a!=c,a>=b&&a>=c,a<=b&&a<=c);
    printf("%d,%d\n",a<=b||a>=c,a==b||b==c);
    printf("%d,%d,%d,%d\n",!(a==b),!(a>=b),!(a>=c),!(a<=b));
    return 0;
 } 

 

 

 

/*Thhis is first C program*/
# include
int main()
{
    printf("headbchsajhcuiknlxkns");
    return 0;
}

 

 

 

/*求两个整数的乘积*/ 
# include
int product(int,int);
int main(void)
{
    int x,y,s;
    scanf("%d %d",&x,&y);
    s=product(x,y);
    printf("The mul is:%d",s);
    return 0;
 } 
 int product(int a,int b)
 {
    int mul;
    mul=a*b;
    return mul;
 }

 

 

 

# include 
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;
}

 

 

 

 

 

/*整数相除*/ 
# include
int main()
{
    int a=5,b=7,c=100,d,e,f;
    d=a/b*c;
    e=a*c/b;
    f=c/b*a;
    printf("d=%d,e=%d,f=%d\n",d,e,f);
    return 0;
 } 

 

 

 

 

/*自加、自减运算*/ 
# include
int main()
{
    int a=5,b=8;
    printf("a++=%d\n",a++);
    printf("a=%d\n",a);
    printf("++b=%d\n",++b);
    printf("b=%d\n",b);
    return 0;
 }