【c++ 重载】

重载"[]":

#include <iostream>
#include <string>
using namespace std;
struct Node{
    #define N 1000
    int data[N], cnt;
    string s[N];
    Node(int c = 0):cnt(c){}
    int &operator[](string str) {
        for(int i = 1; i <= cnt; i++) {
            if(s[i] == str) {
                return data[i];
            }
        }
        data[++cnt] = 0;
        s[cnt] = str;
        return data[cnt];
    }
};
int main()
{
    Node a;
    a["abc"] = 1;
    a["ab"] = 2;
    cout<< a["a"] <<endl<< a["ab"]<< endl<< a["abc"]<< endl;
}
//结果：
//0
//2
//1