Airport

from collections import defaultdict, deque

def airport():
    n, m = map(int, input().split())

    checkpoint_capacity = list(map(int, input().split()))
    checkpoint_capacity.insert(0, 0)
    graph = defaultdict(lambda: defaultdict(int))

    for _ in range(m):
        a, b = map(int, input().split())
        if checkpoint_capacity[a] != -1 and checkpoint_capacity[b] != -1:
            graph[a][b] += min(checkpoint_capacity[a], checkpoint_capacity[b])
        elif checkpoint_capacity[a] != -1:
            graph[a][b] += checkpoint_capacity[a]
        elif checkpoint_capacity[b] != -1:
            graph[a][b] += checkpoint_capacity[b]
        else:
            graph[a][b] = float('inf')
    
    def find_path(source, sink, visited, min_cap):
        if source == sink:
            return min_cap
        
        visited.add(source)
                
        for neighbor, capacity in list(graph[source].items()):
            if neighbor not in visited and capacity > 0:
                flow = find_path(neighbor, sink, visited, min(min_cap, capacity))
                
                if flow > 0:
                    graph[source][neighbor] -= flow
                    graph[neighbor][source] += flow
                    return flow
        
        return 0
    
    max_flow = 0
    while True:
        flow = find_path(1, n, set(), float('inf'))
        if flow == 0:
            break
        max_flow += flow
    
    print(max_flow)  
    

    

if __name__ == "__main__":
    airport()

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: WRONG ANSWER

Test 13

Verdict: WRONG ANSWER