Submission details
Task:Download Speed
Sender:francden
Submission time:2025-10-13 19:45:07 +0300
Language:Python3 (PyPy3)
Status:READY
Result:
Test results
testverdicttime
#1ACCEPTED0.04 sdetails
#20.07 sdetails
#3ACCEPTED0.04 sdetails
#4ACCEPTED0.04 sdetails
#50.07 sdetails
#6--details
#7--details
#80.07 sdetails
#9ACCEPTED0.04 sdetails
#10ACCEPTED0.04 sdetails
#110.07 sdetails
#120.07 sdetails

Code

n,m = [int(x) for x in input().split()]

connections = []
neighbors = []
for i in range(n):
    connections.append([0 for i in range(n)])
    neighbors.append([])

max_conn = 0
for i in range(m):
    a,b,c = [int(x) for x in input().split()]
    if not(b-1 in neighbors[a-1]):
        neighbors[a-1].append(b-1)
        neighbors[b-1].append(a-1)
    connections[a-1][b-1]=c
    max_conn = max(c,max_conn)

def search(L,mini,c):
    last_summit = L[-1]
    for node in neighbors[last_summit]:
        
        if not(node in L):
            curr_connection = connections[last_summit][node]
            if curr_connection >= c:
                if node == n-1:
                    mini = min(curr_connection,mini)
                    return L+[node],mini,False
                mini = min(curr_connection,mini)
                path,mini,flag = search(L+[node],mini,c)
                if flag==False:
                    return path,mini,False
            
    return [],0,True

def find_path():
    #TODO
    c = max_conn//2
    flag = True
    while flag and c>=1:
        L,mini,flag = search([0],float('inf'),c)
        c//=2
    return L,mini

def sub_mini_from_path(path,mini):
    for i in range(len(path)-1):
        connections[path[i]][path[i+1]]-=mini
        connections[path[i+1]][path[i]]+=mini


def find_max():
    curr_max = 0
    for i in range(n):
        for node in neighbors[i]:
            if connections[i][node]>curr_max:
                curr_max = connections[i][node]
    return(curr_max)

curr_path,mini = find_path()

total_flow = mini
while curr_path:
    sub_mini_from_path(curr_path,mini)
    curr_path,mini = find_path()
    total_flow+=mini

print(total_flow)

Test details

Test 1

Verdict: ACCEPTED

input
4 3
1 2 5
2 3 3
3 4 6

correct output
3

user output
3

Test 2

Verdict:

input
4 5
1 2 1
1 3 1
2 3 1
2 4 1
...

correct output
2

user output
(empty)

Error:
Traceback (most recent call last):
  File "input/code.py", line 58, in <module>
    curr_path,mini = find_path()
  File "input/code.py", line 42, in find_path
    return L,mini
UnboundLocalError: local variable 'L' referenced before assignment

Test 3

Verdict: ACCEPTED

input
4 5
1 2 1000000000
1 3 1000000000
2 3 1
2 4 1000000000
...

correct output
2000000000

user output
2000000000

Test 4

Verdict: ACCEPTED

input
2 1
2 1 100

correct output
0

user output
0

Test 5

Verdict:

input
2 1000
1 2 1000000000
1 2 1000000000
1 2 1000000000
1 2 1000000000
...

correct output
1000000000000

user output
1000000000

Test 6

Verdict:

input
500 998
1 2 54
1 3 59
1 4 83
2 5 79
...

correct output
60

user output
(empty)

Test 7

Verdict:

input
500 998
1 2 530873053
1 3 156306296
1 4 478040476
3 5 303609600
...

correct output
1093765123

user output
(empty)

Test 8

Verdict:

input
2 1
1 2 1

correct output
1

user output
(empty)

Error:
Traceback (most recent call last):
  File "input/code.py", line 58, in <module>
    curr_path,mini = find_path()
  File "input/code.py", line 42, in find_path
    return L,mini
UnboundLocalError: local variable 'L' referenced before assignment

Test 9

Verdict: ACCEPTED

input
4 5
1 2 3
2 4 2
1 3 4
3 4 5
...

correct output
6

user output
6

Test 10

Verdict: ACCEPTED

input
4 5
1 2 1
1 3 2
3 2 1
2 4 2
...

correct output
3

user output
3

Test 11

Verdict:

input
10 999
1 2 1000000000
1 2 1000000000
1 2 1000000000
1 2 1000000000
...

correct output
111000000000

user output
1000000000

Test 12

Verdict:

input
7 9
1 2 1
1 3 1
1 4 1
2 5 1
...

correct output
2

user output
(empty)

Error:
Traceback (most recent call last):
  File "input/code.py", line 58, in <module>
    curr_path,mini = find_path()
  File "input/code.py", line 42, in find_path
    return L,mini
UnboundLocalError: local variable 'L' referenced before assignment