comefrom: <awangdev>55. Jump Game_2.java
code: public boolean canJump(int[] nums) {
          if (nums == null || nums.length == 0) return true;
          int n = nums.length, lastPos = n - 1;
          for (int i = lastPos; i >= 0; i--) { 
              if (i + nums[i] >= lastPos) lastPos = i;
          }
          return lastPos == 0;
      }
masked: public boolean var_0 ( int [ ] var_1 ) {
    if ( var_1 == null || var_1 . length == 0 ) return true ;
    int var_2 = var_1 . length , var_3 = var_2 - 1 ;
    for ( int var_4 = var_3 ;
    var_4 >= 0 ;
    var_4 -- ) {
      if ( var_4 + var_1 [ var_4 ] >= var_3 ) var_3 = var_4 ;
    }
    return var_3 == 0 ;
  }
  