全 MyString

 #include <cstdlib>

    
 #include <iostream>
    
 using namespace std;
    
 int strlen(const char * s) 
    
 {	int i = 0;
    
 	for(; s[i]; ++i);
    
 	return i;
    
 }
    
 void strcpy(char * d,const char * s)
    
 {
    
 	int i = 0;
    
 	for( i = 0; s[i]; ++i)
    
 		d[i] = s[i];
    
 	d[i] = 0;
    
 		
    
 }
    
 int strcmp(const char * s1,const char * s2)
    
 {
    
 	for(int i = 0; s1[i] && s2[i] ; ++i) {
    
 		if( s1[i] < s2[i] )
    
 			return -1;
    
 		else if( s1[i] > s2[i])
    
 			return 1;
    
 	}
    
 	return 0;
    
 }
    
 void strcat(char * d,c