自学C语言有点简单的不懂,求指导
#include<stdio.h>
int mul(int a, int b);
main()
{
int a,b,c;
a = 5;
b = 10;
c = mul(a,b);
printf("multiplication of %d and %d is %d",a,b,c);
}
int mul(int x, int y);
int p;
{
p = x*y;
return p;
}
编译过后总是显示:“18 1 F:\源代码\子程序的使用.cpp [Error] expected unqualified-id before ‘{’ token”。请问是什么问题?