Submission details
Task:Distinct Routes
Sender:aalto26gm_030
Submission time:2026-10-19 17:36:07 +0300
Language:Python3 (PyPy3)
Status:READY
Result:ACCEPTED
Test results
testverdicttime
#1ACCEPTED0.04 sdetails
#2ACCEPTED0.04 sdetails
#3ACCEPTED0.10 sdetails
#4ACCEPTED0.05 sdetails
#5ACCEPTED0.04 sdetails
#6ACCEPTED0.06 sdetails
#7ACCEPTED0.06 sdetails
#8ACCEPTED0.06 sdetails
#9ACCEPTED0.04 sdetails
#10ACCEPTED0.04 sdetails
#11ACCEPTED0.04 sdetails
#12ACCEPTED0.04 sdetails
#13ACCEPTED0.04 sdetails
#14ACCEPTED0.04 sdetails
#15ACCEPTED0.07 sdetails

Code

import sys
from collections import deque

sys.setrecursionlimit(2000)

class Edge:
    def __init__(self, to, cap, rev):
        self.to = to
        self.cap = cap
        self.flow = 0
        self.rev = rev

def add_edge(adj, u, v, cap):
    a = Edge(v, cap, len(adj[v]))
    b = Edge(u, 0, len(adj[u]))
    adj[u].append(a)
    adj[v].append(b)

def bfs(adj, s, t, parent):
    visited = [False] * len(adj)
    queue = deque([s])
    visited[s] = True
    
    while queue:
        u = queue.popleft()
        if u == t:
            return True
        for i, edge in enumerate(adj[u]):
            if not visited[edge.to] and edge.cap - edge.flow > 0:
                visited[edge.to] = True
                parent[edge.to] = (u, i)
                queue.append(edge.to)
                
    return False

def max_flow(adj, s, t):
    total_flow = 0
    parent = [None] * len(adj)
    
    while bfs(adj, s, t, parent):
        push = float('inf')
        curr = t
        while curr != s:
            p_node, p_edge_idx = parent[curr]
            edge = adj[p_node][p_edge_idx]
            push = min(push, edge.cap - edge.flow)
            curr = p_node
            
        curr = t
        while curr != s:
            p_node, p_edge_idx = parent[curr]
            edge = adj[p_node][p_edge_idx]
            edge.flow += push
            adj[edge.to][edge.rev].flow -= push
            curr = p_node
            
        total_flow += push
        
    return total_flow

def main():
    input_data = sys.stdin.read().split()
    if not input_data:
        return
        
    n = int(input_data[0])
    m = int(input_data[1])
    
    adj = [[] for _ in range(n + 1)]
    
    idx = 2
    for _ in range(m):
        u = int(input_data[idx])
        v = int(input_data[idx + 1])
        add_edge(adj, u, v, 1)
        idx += 2
        
    s, t = 1, n
    k = max_flow(adj, s, t)
    
    print(k)
    
    for _ in range(k):
        path = [1]
        curr = 1
        
        while curr != t:
            for edge in adj[curr]:
                if edge.flow > 0:
                    edge.flow -= 1  
                    curr = edge.to
                    path.append(curr)
                    break
                    
        print(len(path))
        print(*(path))

main()

Test details

Test 1

Verdict: ACCEPTED

input
2 1
1 2

correct output
1
2
1 2 

user output
1
2
1 2

Test 2

Verdict: ACCEPTED

input
4 2
1 2
3 4

correct output
0

user output
0

Test 3

Verdict: ACCEPTED

input
500 996
1 2
2 500
1 3
3 500
...

correct output
498
3
1 2 500 
3
1 3 500 
...

user output
498
3
1 2 500
3
1 3 500
...

Test 4

Verdict: ACCEPTED

input
500 499
1 2
2 3
3 4
4 5
...

correct output
1
500
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

user output
1
500
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

Test 5

Verdict: ACCEPTED

input
2 1
2 1

correct output
0

user output
0

Test 6

Verdict: ACCEPTED

input
40 1000
25 22
15 24
7 33
16 32
...

correct output
21
44
1 35 39 34 29 32 22 38 20 30 1...

user output
21
3
1 35 40
3
1 3 40
...

Test 7

Verdict: ACCEPTED

input
75 1000
72 6
46 66
63 45
70 46
...

correct output
12
30
1 29 24 9 18 63 45 31 66 72 6 ...

user output
12
5
1 29 49 14 75
4
1 70 12 75
...

Test 8

Verdict: ACCEPTED

input
100 1000
75 97
7 62
88 25
36 44
...

correct output
9
51
1 35 15 86 79 34 43 94 83 75 9...

user output
9
4
1 35 23 100
5
1 62 25 28 100
...

Test 9

Verdict: ACCEPTED

input
3 2
1 2
2 3

correct output
1
3
1 2 3 

user output
1
3
1 2 3

Test 10

Verdict: ACCEPTED

input
11 12
1 2
2 3
3 4
4 5
...

correct output
2
6
1 2 3 4 5 11 
7
1 6 7 8 9 10 11 

user output
2
6
1 2 3 4 5 11
7
1 6 7 8 9 10 11

Test 11

Verdict: ACCEPTED

input
8 9
1 2
2 3
3 8
1 4
...

correct output
2
5
1 2 6 7 8 
5
1 4 5 3 8 

user output
2
5
1 2 6 7 8
5
1 4 5 3 8

Test 12

Verdict: ACCEPTED

input
8 9
1 2
1 3
2 3
3 4
...

correct output
1
8
1 2 3 4 5 6 7 8 

user output
1
7
1 3 4 5 6 7 8

Test 13

Verdict: ACCEPTED

input
7 9
1 2
1 3
2 7
3 4
...

correct output
3
3
1 2 7 
4
1 3 5 7 
...

user output
3
3
1 2 7
4
1 3 4 7
...

Test 14

Verdict: ACCEPTED

input
7 15
3 6
5 2
5 4
3 5
...

correct output
2
5
1 2 3 6 7 
4
1 4 5 7 

user output
2
5
1 2 3 6 7
6
1 4 5 2 5 7

Test 15

Verdict: ACCEPTED

input
500 986
244 252
224 22
81 484
273 432
...

correct output
116
5
1 129 142 473 500 
5
1 63 158 171 500 
...

user output
116
5
1 129 142 473 500
5
1 63 158 171 500
...