1. Read in input, store it in 2 arrayLists, one with the x coordinates and one with the y coordinates

// Point 1 is top point
// First find the top most point
Loop through all the points and find the index of the point with the maximum y coordinate
int max = 0;
for (int i=0; i<N; i++) {
  if (y.get(i) >y.get(max)) {
    max = i;
  }
}

// Find the area if we remove the top most point - loop through all the points except max and find maxx, minx, maxy, and miny