Reading data to make adjacency list with two weights

I'm making an adjacency list to represent a graph of roads, there are two kinds of weights (length and capacity) and for some reason this code never exits the for loop. it gets stuck on the cin for the last line. input is in the form:

4 5 4
0 1 1 5
0 2 1 4
1 2 2 2
1 3 1 4
2 3 1 5

I'm a student starting out. Help is very much appreciated thank you.

#include <iostream>
#include <vector>
using namespace std;

int N, M, T; //#cities N, #highways M, time available T

struct Road {
    int Y, L, C; //destination Y, length L and capacity C
};

void readNetwork(vector<vector<Road>> &adjList) {
    cin >> N >> M >> T;
    adjList.resize(N);
    for (int i = 0; i < M; i++){
        int x, y, l, c;
        cin >> x >> y >> l >> c;
        adjList[x].push_back({y,l,c});
    }
}

int main() {
    
    vector<vector<Road>> adjList;

    readNetwork(adjList);
    cout << adjList.size();

    return 0;
};