题解 | #查找两个字符串a,b中的最长公共子串#

#include <iostream>
using namespace std;

int main() {
    string a;
    string b;
    getline(cin, a);
    getline(cin, b);
    string tem;
    string res;
    if (a.size() > b.size()) {
        for (int i = 0, j = 0; j < b.size();) {
            tem = b.substr(i, len);
            if (a.find(tem) == a.npos) {
                i++;
                j = i + len;
            } else {
                res = tem;
                j++;
                len++;
            }
        }
    } else {
        for (int i = 0, j = 0; j < a.size();) {
            tem = a.substr(i, len);
            if (b.find(tem) == b.npos) {
                i++;
                j = i + len;
            } else {
                res = tem;
                j++;
                len++;
            }
        }
    }
cout << res;
}

从短的字符串中获取子字符串，然后去长的字符串中找该短的字符串，找到的话让子字符串长度+1再去找，没找到就长度不变，子字符开头向后移一位去找。