比较字符串大小strcmp

#include <iostream>
#include <assert.h>
using namespace std;

//比较字符串大小 s - t
int strcmp(const char *s, const char *t)
{
	assert(s != NULL && t != NULL);    //断言保证传进来的参数不是空
	while (*s && *t && *s == *t)     //保证两者还有指向内容，并且相等
	{
		++s;
		++t;
	}
	return (*s - *t);
}

int main(void)
{
    char *s = "hello world";
	char *t = "hello";
	//char a[10] = {0};
	cout<<strcmp(s,t);//32
	char r = ' ';
	cout<<int(r);//空格的值是32
    system("pause");
    return 0;
}