1306

class Solution {
public:
    bool canReach(vector<int>& arr, int start) {
        queue<int> q;
        int sz = arr.size();
        bool vis[arr.size()];
        memset(vis, 0, sizeof(vis));

        q.push(start);
        vis[start] = true;
        while(!q.empty()){
            int idx  = q.front();
            q.pop();
            if(arr[idx] == 0) return true;
            int next = idx+arr[idx];
            if(next < sz && next >= 0  && !vis[next]){
                q.push(next);
                vis[next] = true;
            }
            next = idx-arr[idx];
            if(next < sz && next >= 0  && !vis[next]){
                q.push(next);
                vis[next] = true;
            }
        }
        return false;
    }
};