Problem p03608 (python)

Fixed submission:
import sys,queue,math,copy,itertools,bisect,collections,heapq

def main():
    sys.setrecursionlimit(10**7)
    INF = 10**8
    MOD = 10**9 + 7
    LI = lambda : [int(x) for x in sys.stdin.readline().split()]
    _LI = lambda : [int(x)-1 for x in sys.stdin.readline().split()]
    NI = lambda : int(sys.stdin.readline())

    N,M,R = LI()
    r = _LI()
    root = [[] for _ in range(N)]
    for _ in range(M):
        a,b,c = LI()
        root[a-1].append((b-1,c))
        root[b-1].append((a-1,c))

    memo = [[0] * N for _ in range(N)]

    min_r = INF
    for x in itertools.permutations(r):
        it = 0
        s = x[0]
        for t in x[1:]:
            if memo[s][t]:
                it += memo[s][t]
            else:
                node = [INF] * N
                q = collections.deque()
                q.append((s,0))
                node[s] = 0
                while q:
                    u,l = q.popleft()
                    for v,m in root[u]:
                        if node[v] > l + m:
                            node[v] = l + m
                            q.append((v,l+m))
                memo[s][t] = node[t]
                memo[t][s] = node[t]
                it += node[t]
            s = t
        min_r = min(min_r,it)
    print(min_r)

if __name__ == '__main__':
    main()

Buggy submission (verdict: Runtime Error):
import sys,queue,math,copy,itertools,bisect,collections,heapq

def main():
    sys.setrecursionlimit(10**7)
    INF = 10**8
    MOD = 10**9 + 7
    LI = lambda : [int(x) for x in sys.stdin.readline().split()]
    _LI = lambda : [int(x)-1 for x in sys.stdin.readline().split()]
    NI = lambda : int(sys.stdin.readline())

    N,M,R = LI()
    r = _LI()
    root = [[] for _ in range(N)]
    for _ in range(M):
        a,b,c = LI()
        root[a-1].append((b-1,c))
        root[b-1].append((a-1,c))

    memo = [[0] * R for _ in range(R)]

    min_r = INF
    for x in itertools.permutations(r):
        it = 0
        s = x[0]
        for t in x[1:]:
            if memo[s][t]:
                it += memo[s][t]
            else:
                node = [INF] * N
                q = [(s,0)]
                while q:
                    u,l = q.pop()
                    node[u] = l
                    for v,m in root[u]:
                        if node[v] > l + m:
                            q.append((v,l+m))
                memo[s][t] = node[t]
                memo[t][s] = node[t]
                it += node[t]
            s = t
        min_r = min(min_r,it)
    print(min_r)

if __name__ == '__main__':
    main()

Buggy submission (verdict: Runtime Error):
import sys,queue,math,copy,itertools,bisect,collections,heapq

def main():
    sys.setrecursionlimit(10**7)
    INF = 10**8
    MOD = 10**9 + 7
    LI = lambda : [int(x) for x in sys.stdin.readline().split()]
    _LI = lambda : [int(x)-1 for x in sys.stdin.readline().split()]
    NI = lambda : int(sys.stdin.readline())

    N,M,R = LI()
    r = _LI()
    root = [[] for _ in range(N)]
    for _ in range(M):
        a,b,c = LI()
        root[a-1].append((b-1,c))
        root[b-1].append((a-1,c))

    memo = [[0] * r for _ in range(R)]

    min_r = INF
    for x in itertools.permutations(r):
        it = 0
        s = x[0]
        for t in x[1:]:
            if memo[s][t]:
                it = memo[s][t]
            else:
                node = [INF] * N
                q = [(s,0)]
                while q:
                    u,l = q.pop()
                    node[u] = l
                    for v,m in root[u]:
                        if node[v] > l + m:
                            q.append((v,l+m))
                it += node[t]
                memo[s][t] = node[t]
                memo[t][s] = node[t]
            s = t
        min_r = min(min_r,it)
    print(min_r)
    
if __name__ == '__main__':
    main()

Buggy submission (verdict: Runtime Error):
import sys,queue,math,copy,itertools,bisect,collections,heapq

def main():
    sys.setrecursionlimit(10**7)
    INF = 10**8
    MOD = 10**9 + 7
    LI = lambda : [int(x) for x in sys.stdin.readline().split()]
    _LI = lambda : [int(x)-1 for x in sys.stdin.readline().split()]
    NI = lambda : int(sys.stdin.readline())

    N,M,R = LI()
    r = _LI()
    root = [[] for _ in range(N)]
    for _ in range(M):
        a,b,c = LI()
        root[a-1].append((b-1,c))
        root[b-1].append((a-1,c))

    memo = [[0] * r for _ in range(R)]

    min_r = INF
    for x in itertools.permutations(r):
        it = 0
        s = x[0]
        for t in x[1:]:
            if memo[s][t]:
                it = memo[s][t]
            else:
                node = [INF] * N
                q = [(s,0)]
                while q:
                    u,l = q.pop()
                    node[u] = l
                    for v,m in root[u]:
                        if node[v] > l + m:
                            q.append((v,l+m))
                it += node[t]
                memo[s][t] = node[t]
                memo[t][s] = node[t]
            s = t
        min_r = min(min_r,it)
    print(min_r)
    
if __name__ == '__main__':
    main()