Problem link:https://lightoj.com/problem/penguins. I solved this problem and my verdict is Ac. My idea is I will take every ice bar as sink and calculate max flow. If max flow equal to total number of penguins then this bar is a one where all penguins can met.I use dinic with scaling for calculating max flow. According to my solution complexity should be n*(nmlogU) here m=is number of edge and U is maximum flow value.Again m=n^2 is possible in this problem. So total complexity considering test case should be test*n^4*logU.Which shouldn’t pass test case according to me,but my verdict is Ac. Is this happen for weak test set?