第二个例子还可以这样写
#include <stdio.h>
int main()
{
    int x,y;
    printf("please input x and y\n");
    scanf("%d%d",&x,&y);
    printf("%d * %d = %d\n",x,y,(x*y));
    return 0;
}
对不?大家一起学......

加油，不过貌似油价又涨了，省着点加哦

谢谢！！！

发现了，谢谢哈

不错哈

学习了

第三个程序
#include<stdio.h>
main()
{
   float x,y,c;
   printf("Please input x and y :\n");
   scanf("%f%f",&x,&y);
   c=x>y?x:y;
   printf("MAX of (%f,%f) is %f",x,y,c);
 }

#include <stdio.h>
void main ()
{
    printf("Hello World!\n");

}   
求教这个哪里错了......

需不需要加void

#include<stdio.h>
main()
{
   char ch,nch;
   int count,k;
   printf("Please input a string with a # in the end.\n");
   scanf("%c",&ch);
   while(ch!="#")
    {
       if(ch>='0'&&ch<='9')           
          {
              count=ch-'0'+1;
              scanf("%c",&nch);
              for(k=0;k<count;k++)
                 printf("%c",nch);
           }
        else
           printf("%c",ch);
        printf(" ");
        scanf("%c",&ch);
     }
     pringf("#\n");
}
请问ch>='0'&&ch<='9'和count=ch-'0'+1什么意思，谢谢!