public static int boardCutting(List<Integer> cost_y, List<Integer> cost_x) {
// Write your code here
long minCost = 0;
Collections.sort(cost_y, Comparator.reverseOrder());
Collections.sort(cost_x, Comparator.reverseOrder());
long hp = 1;
long vp = 1;
int hi = 0;
int vi = 0;
while(hi < cost_y.size() && vi < cost_x.size()){
    if(cost_y.get(hi) > cost_x.get(vi)){
        minCost = minCost + vp*cost_y.get(hi);
        hp++;
        hi++;
    } else {
        minCost = minCost + hp*cost_x.get(vi);
        vi++;
        vp++;
    }
}
while(hi < cost_y.size()){
    minCost = minCost + vp*cost_y.get(hi);
    hi++;
}
while(vi< cost_x.size()){
     minCost = minCost + hp*cost_x.get(vi);
    vi++;
}

return (int)(minCost%1000000007);
}