实验1c语言开发环境使用和数据类型，运算符和表达式

/*this is first c program*/
# include<stdio.h>
int main()
{
    printf("Hello Mars!");
    return ;
}
#include<stdio.h>
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 ;
}
int product(int a,int b)
{
    int mul;
    mul=a*b;
    return mul;
}
#include <stdio.h>
int main()
{
    int a=,b=,c=,d,e,f;
    d=a/b*c;
    e=a*c/b;
    f=c/b*a;
    printf("d=%d,e=%e,f=%d\n",d,e,f);
    return ;

}
#include<stdio.h>
int main()
{
    int a=,b=;
    printf("a++=%d\n",a++);
    printf("a=%d\n",a);
    printf("++b=%d\n,++b");
    printf("b=%d\n",b);
    return ;
}
#include<stdio.h>
int main()
{
    int a= ,b=,c=;
    printf("%d,%d,%d,%d\n",a==b&&a==c,a!=b&&a!=c,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>=c),!(a<=b));
   return ;
}
#include<stdio.h>
int main ()
{
    int x;
    printf("输入一个整数\n");
    scanf("%d",&x);

    if(x%==)
        printf("是偶数\n");
    else

    printf("是奇数\n");
    return  ;
}
#include<stdio.h>
int main(){
    char ch;
    printf("输入一个字符:\n");
    scanf("%c",&ch);
    if(ch<='z'&&ch>='a')
    printf("%c-->%c",ch,ch-) ;
    else
    printf("%c不是小写字母\n",ch);
}