金海佳学C++primer 练习9.43

string中替换oldVal->newVal

Practice 9.43

#include <iostream>#include <queue>#include <string>#include <vector>#include <algorithm>#include <list>#include <iterator>#include <cmath>#include <cstring>#include <forward_list>#include <sstream>using namespace std;bool ok(string::iterator it1, string s2) {    auto it2 = s2.begin();    while(it2 != s2.end()) {        if(*it1 != *it2) break;        it1++, it2++;    }    if(it2 == s2.end()) return true;    else return false;}void old2new(string & s, string oldVal, string newVal) {    auto it = s.begin();    int len_old = (int)oldVal.length();    while(it != s.end()) {        if(ok(it, oldVal)) {            s.erase(it,it+len_old);            s.insert(it,newVal.begin(),newVal.end());               }        else {            ++it;        }    }   }int main() {    string s, oldVal, newVal;    cin >> s >> oldVal >> newVal;    old2new(s,oldVal,newVal);    cout << "s: " << s << endl;    cout << "old: " << oldVal << endl;    cout << "new: " << newVal << endl;    cout << s << endl;    return 0;}

Ouput

s: jinwanglangjiaold: hainew: wanglangjinwanglangjia

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