超时错误，可能是无限循环C ++

Question

以下代码使用Xcode 100％工作，但是当我使用Autograder运行代码时，我收到了以下错误Time out error, probably infinite loop C++，如下图所示。

这是否意味着我的阵列太小了？

输入：

4 6

女性保守派新保守派退伍军人

特朗普女士1

特朗普保守党1

特朗普新保守派5

女性Neocons 1

Neocons Veterans 5

保守派退伍军人1

输出：

8

这是我的代码：

#include <iostream>
#include <algorithm>
#include <string>
#include <stdlib.h>
#include <vector>
#include <ctime>
#include <map>

using namespace std;
/*map Group Name to a Integer
  useful for representation of graph
*/
map <string, int> nameToNumber;
/*
 adjacency matrix to represent graph
 this will work since number of nodes is less
  */
int graph[301][301];
/*
   recursion to find if target is reachable from src in graph
   par == parent of src.. useful to keep track of visited nodes
 */

bool reachable(int src, int target, int par = -1)
{
    if (src == target) return true;

    bool isReachable = false;

    for (int i = 0; i < 100; ++i)
    {
        if (i != par && graph[src][i] != 0 && reachable(i, target, src))
        {
            isReachable = true;
        }
    }
    return isReachable;
}

int main()
{
    int n, m;
    cin >> n >> m;
    // add names to map
    for (int i = 0; i < n; ++i) {
        string name;
        cin >> name;
        nameToNumber[name] = i;
    }

    vector <pair<int, pair<int, int>>> edges;
    // input edges
    for (int i = 0; i < m; ++i)
    {
        string u, v; int w;
        cin >> u >> v >> w;
        edges.push_back(make_pair(w, make_pair(nameToNumber[v], nameToNumber[u])));
    }
    // sort edges based in increasing weights
    sort(edges.begin(), edges.end());

    int cost = 0;
    for (int i = 0; i < edges.size(); ++i) {
        int u = edges[i].second.first;
        int v = edges[i].second.second;
        int w = edges[i].first;
    // check if u-v edge causes cycle

        if (!reachable(u, v)) {
            graph[u][v] = 1;
            cost += w;
        }
    }

    cout << cost ;

    return 0;
}

每次我使用Autograder运行我的代码时都会收到以下错误Time out error, probably infinite loop。

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