1345

class Solution {
public:
    int minJumps(vector<int>& arr) {
        int n = arr.size();
        unordered_map<int, vector<int>> indicesOfValue;
        for (int i = 0; i < n; i++)
            indicesOfValue[arr[i]].push_back(i);
        vector<bool> visited(n); visited[0] = true;
        queue<int> q; q.push(0);
        int step = 0;
        while (!q.empty()) {
            int sz = q.size();
            while(sz--) {
                int i = q.front(); q.pop();
                if (i == n - 1) return step; // Reached to last index
                if(i-1 >= 0 && !visited[i-1]){
                    q.push(i-1);
                    visited[i-1] = true;
                }
                if(i+1 < n && !visited[i+1]){
                    q.push(i+1);
                    visited[i+1] = true;
                }
                for(int j:indicesOfValue[arr[i]]) {
                    if(j >= 0 && j < n && !visited[j]) {
                        visited[j] = true;
                        q.push(j);
                    }
                }
                // Very important step to clear the array, else will get TLE.
                indicesOfValue[arr[i]].clear();
            }
            step++;
        }
        return 0;
    }
};