题解 | #找出直系亲属#

//递归暴力解

#include <iostream>
using namespace std;
int n, m;
string list[100];

int dfs(char a, char b, int deep) {
    for (int i = 0; i < n; i++) {
        if (a == list[i][0]) {
            if (b == list[i][1] || b == list[i][2])
                return deep;
            int i1 = dfs(list[i][1], b, deep + 1);
            int i2 = dfs(list[i][2], b, deep + 1);
            return i1 > i2 ? i1 : i2;
        }
    }
    return 0;
}

int main() {

    while (cin >> n >> m) { // 注意 while 处理多个 case

        for (int i = 0; i < n; i++) {
            cin >> list[i];
        }
        for (int i = 0; i < m; i++) {
            char a, b;
            cin >> a >> b;
            int i1 = -dfs(a, b, 1);
            int i2 = dfs(b, a, 1);
            int deep = i1 != 0 ? i1 : i2;
            switch (deep) {
                case 0:
                    cout << "-" << endl;
                    break;
                case 1:
                    cout << "parent" << endl;
                    break;
                case -1:
                    cout << "child" << endl;
                    break;
                case 2:
                    cout << "grandparent" << endl;
                    break;
                case -2:
                    cout << "grandchild" << endl;
                    break;
                default:
                    for (int p = 2; p < abs(deep); p++) {
                        cout << "great-";
                    }
                    if (deep > 0)
                        cout << "grandparent" << endl;
                    else
                        cout << "grandchild" << endl;
            }
        }
    }
}
// 64 位输出请用 printf("%lld")