# 1791. Find Center of Star Graph

There is an undirected star graph consisting of n nodes labeled from 1 to n. A star graph is a graph where there is one center node and exactly n - 1 edges that connect the center node with every other node.

You are given a 2D integer array edges where each edges\[i] = \[ui, vi] indicates that there is an edge between the nodes ui and vi. Return the center of the given star graph.

Example 1:

Input: edges = \[\[1,2],\[2,3],\[4,2]] Output: 2 Explanation: As shown in the figure above, node 2 is connected to every other node, so 2 is the center. Example 2:

Input: edges = \[\[1,2],\[5,1],\[1,3],\[1,4]] Output: 1

Constraints:

3 <= n <= 105 edges.length == n - 1 edges\[i].length == 2 1 <= ui, vi <= n ui != vi The given edges represent a valid star graph.

## Solutions

1. **straight forward**

```cpp
class Solution {
public:
    int findCenter(vector<vector<int>>& edges) {
        int maxn = 0;
        vector<int> degree(1e5 + 1);
        for (auto & e : edges) {
            degree[e[0]]++;
            degree[e[1]]++;
            maxn = max(maxn, max(e[0], e[1]));
        }
        for (int i = 0; i < degree.size(); i++) {
            if (degree[i] == maxn - 1)
                return i;
        }
        return 0;
    }
};
```