题解 | #单词替换#

要考虑的情况比较多，针对测试案例多改，写于2024.3.20

#include <iostream>
#include <algorithm>
#include <cstring>
#include <cmath>
using namespace std;

int main()
{
    int n, i, position;
    string s, a, b;
    string temp;
    getline(cin, s);
    getline(cin, a);
    getline(cin, b);
    // cout << s << "hdu" << a << "hdu" << b;
    // position = s.find(a);
    while (s.find(a) != string::npos)
    {
        // cout << position;
        // temp = s.substr(position, a.size() + 1);
        position = s.find(a);
        if (position != 0 && s[position + a.size()] == ' ' && s[position - 1] == ' ' || position == 0 && s[position + a.size()] == ' ')
        {
            s.erase(position, a.size());
            s.insert(position, b);
        }
        else
        {
            s.erase(position, a.size());
            for (i = 0; i < a.size(); i++)
            {
                s.insert(position, "*");
            }
        }
        // position = s.find(a);
    }
    // cout << s << endl;
    while (s.find("*") != string::npos)
    {
        position = s.find("*");
        s.erase(position, a.size());
        s.insert(position, a);
    }

    cout << s << endl;

    return 0;
}