char类型字符数组

char 字符数组相关方法

```//1、strlen(s1)
//cout<<strlen(s1)<<" "<<strlen(s2)<<endl;
//2、s1和s2比大小 strcmp(s1,s2)
//strcmp(s1,s2)>0 s1大于s2
// strcmp(s1,s2)==0 s1等于s2
// strcmp(s1,s2)<0 s1小于s2
//cout<< strcmp(s1,s2)<<endl;
//3、将s2的字符串连接到s1字符串后面 strcat(s1,s2)
//strcat(s1,s2);
//cout<<s1<<endl; 
//4、将s2的字符串覆盖原s1的字符串strcpy(s1,s2)
//strcpy(s1,s2);
//cout<<s1<<endl;