太久沒用C了，C++string是以‘\0‘結尾,C總char*也是以‘\0‘結尾

但是用string.copy()方法得到的字符串並不是以‘\0結尾

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題目描述

#include <string
 
.h>
#include <algorithm>
#include <vector>
#include <iostream>
#include <string>
using namespace std;
class Solution {
public:
    void replaceSpace(char *str,int length) {
        string strr(str);
        int pos;
        while ((pos = strr.find(" ")) != -1) {
            strr 
 
= strr.erase(pos, 1);
            strr = strr.insert(pos, "%20");
        }
        strr.copy(str, strr.length());
//        strcpy(str,strr.c_str());
        str[strr.length()] = ‘\0‘;
        cout<<str;
    }
};
int main()
{

    Solution demo;
    char s[] = "we are happy!";
    demo.replaceSpace(s, 
 
13);
    return 0;
}

劍指offer--2.替換空格