CSES - Aalto Competitive Programming 2024 - wk7 Homework - Results
Submission details
Task:Download Speed
Sender:ZDHKLV
Submission time:2024-10-10 12:15:10 +0300
Language:C++ (C++11)
Status:READY
Result:ACCEPTED
Test results
testverdicttime
#1ACCEPTED0.00 sdetails
#2ACCEPTED0.00 sdetails
#3ACCEPTED0.00 sdetails
#4ACCEPTED0.00 sdetails
#5ACCEPTED0.00 sdetails
#6ACCEPTED0.01 sdetails
#7ACCEPTED0.01 sdetails
#8ACCEPTED0.00 sdetails
#9ACCEPTED0.00 sdetails
#10ACCEPTED0.00 sdetails
#11ACCEPTED0.00 sdetails
#12ACCEPTED0.00 sdetails

Code

#include <bits/stdc++.h>
using namespace std;

long long max_flow(vector<vector<int>> adj, vector<vector<long long>> capacity,
                   int source, int sink) {

	int n = adj.size();
	vector<int> parent(n, -1);

	auto reachable = [&]() -> bool {
		queue<int> q;
		q.push(source);
		while (!q.empty()) {
			int node = q.front();
			q.pop();
			for (auto y : adj[node]) {
				if (capacity[node][y] <= 0 || parent[y] != -1)
                    continue;
				parent[y] = node;
				q.push(y);
			}
		}
		return parent[sink] != -1;
	};

	long long flow = 0;

	while (reachable()) {

		int node = sink;
		long long current_flow = LONG_LONG_MAX;
		
        while (node != source) {
			current_flow = min(current_flow, capacity[parent[node]][node]);
			node = parent[node];
		}

		node = sink;

		while (node != source) {
			capacity[parent[node]][node] -= current_flow;
			capacity[node][parent[node]] += current_flow;
			node = parent[node];
		}

		flow += current_flow;
		fill(parent.begin(), parent.end(), -1);

	}

	return flow;

}

int main() {

	int n, m;
	cin >> n >> m;

	vector<vector<long long>> capacity(n, vector<long long>(n, 0));
	vector<vector<int>> adj(n);

	for (int i = 0; i < m; i++) {
		int a, b, c;
		cin >> a >> b >> c;
		a--, b--;
		adj[a].push_back(b);
		adj[b].push_back(a);
		capacity[a][b] += c;
	}

	cout << max_flow(adj, capacity, 0, n - 1) << endl;
    
}

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: ACCEPTED

input
4 5
1 2 1
1 3 1
2 3 1
2 4 1
...

correct output
2

user output
2

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: ACCEPTED

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

correct output
1000000000000

user output
1000000000000

Test 6

Verdict: ACCEPTED

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

correct output
60

user output
60

Test 7

Verdict: ACCEPTED

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

correct output
1093765123

user output
1093765123

Test 8

Verdict: ACCEPTED

input
2 1
1 2 1

correct output
1

user output
1

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: ACCEPTED

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

correct output
111000000000

user output
111000000000

Test 12

Verdict: ACCEPTED

input
7 9
1 2 1
1 3 1
1 4 1
2 5 1
...

correct output
2

user output
2