// where i am doing wrong

public static long gridlandMetro(int n, int m, int k, List<List<Integer>> track) {
    Map<Integer,int[]> realPath = new HashMap<>();
    long result = 0;
    for(int i =0;i<k;i++){
        List<Integer> l1 = track.get(i);
        int row = l1.get(0);
        int c1 = l1.get(1);
        int c2 = l1.get(2);
        if(realPath.containsKey(row)){
             int[] coloums = realPath.get(row);
            int c21 = coloums[0];
            int c22 = coloums[1];
            if(c21>c1){
               coloums[0] = c1;
            }
            if(c22<c2){
                coloums[1] = c2;
            }
            realPath.put(row, coloums);
        }else{
            int[] coloums = new int[2];
            coloums[0] = c1;
            coloums[1] = c2;
            realPath.put(row, coloums);
        }
    }
    for(int i =1;i<=n;i++){
        if(realPath.containsKey(i)){
            int[] coloums = realPath.get(i);
            int c21 = coloums[0];
            int c22 = coloums[1];
            int incr = (m+c21)-(c22+1);
            result+=incr;
        }else{
            result+=m;
        }
    }
    return result;
}