oj.uz

Submission #1114955

# Submission time Handle Problem Language Result Execution time Memory
1114955 2024-11-19T20:38:58 Z lucascgar Alternating Current (BOI18_alternating) C++17
19 / 100
 92 ms 9660 KB 
#include <bits/stdc++.h>

using namespace std;

/*

*/

typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long double, long double> pdd;

const int MAXN = 1e5+10;

vector<int> w[MAXN];
bool ty[MAXN];
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    // cout << fixed << setprecision(7);

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

    int a, b;
    for (int i=0;i<m;i++){
        cin >> a >> b;
        if(b<a) return 0;
        w[a].push_back(i);
        w[b].push_back(i);
    }
    set<int> cr;
    int ps=-1, ng=-1;
    bool valid = 1;
    for (int i=1;i<=n;i++){
        vector<int> rm;
        while (!w[i].empty()){
            int u = w[i].back();
            w[i].pop_back();
            if (!cr.count(u) && ps != u && ng != u){
                cr.insert(u);
            }
            else{
                rm.push_back(u);
            }
        }
        if (cr.size() < (int)(ps==-1)+(ng==-1)){
            valid = 0;
            break;
        }

        if (ps==-1){
            ps = *cr.begin();
            cr.erase(cr.begin());
            ty[ps]=0;
        }
        if (ng==-1){
            ng = *cr.begin();
            cr.erase(cr.begin());
            ty[ng]=1;
        }

        for (auto &u:rm){
            cr.erase(u);
            if (ps==u) ps=-1;
            if (ng==u) ng=-1;
        }
    }

    if (!valid){
        cout << "impossible\n";
        return 0;
    }
    for (int i=0;i<m;i++) cout << (int)ty[i];
    cout << '\n';

    return 0;
}

Compilation message

alternating.cpp: In function 'int main()':
alternating.cpp:47:23: warning: comparison of integer expressions of different signedness: 'std::set<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   47 |         if (cr.size() < (int)(ps==-1)+(ng==-1)){
      |             ~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2640 KB Output is correct
2 Correct 1 ms 2640 KB Output is correct
3 Incorrect 1 ms 2640 KB Unexpected end of file - token expected
4 Halted 0 ms 0 KB -

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2640 KB Output is correct
2 Correct 1 ms 2640 KB Output is correct
3 Incorrect 1 ms 2640 KB Unexpected end of file - token expected
4 Halted 0 ms 0 KB -

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2640 KB Output is correct
2 Correct 1 ms 2640 KB Output is correct
3 Incorrect 1 ms 2640 KB Unexpected end of file - token expected
4 Halted 0 ms 0 KB -

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 50 ms 9660 KB Output is correct
2 Correct 2 ms 2640 KB Output is correct
3 Correct 11 ms 6212 KB Output is correct
4 Correct 27 ms 8784 KB Output is correct
5 Correct 35 ms 6984 KB Output is correct
6 Correct 30 ms 6252 KB Output is correct
7 Correct 32 ms 6984 KB Output is correct
8 Correct 3 ms 2896 KB Output is correct
9 Correct 2 ms 2640 KB Output is correct
10 Correct 31 ms 6992 KB Output is correct
11 Correct 34 ms 6472 KB Output is correct
12 Correct 33 ms 6988 KB Output is correct
13 Correct 2 ms 2640 KB Output is correct
14 Correct 2 ms 2640 KB Output is correct
15 Correct 32 ms 5952 KB Output is correct
16 Correct 24 ms 8780 KB Output is correct
17 Correct 92 ms 9032 KB Output is correct
18 Correct 90 ms 7628 KB Output is correct
19 Correct 3 ms 3320 KB Output is correct
20 Correct 24 ms 5456 KB Output is correct

Subtask #5
0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2640 KB Output is correct
2 Correct 1 ms 2640 KB Output is correct
3 Incorrect 1 ms 2640 KB Unexpected end of file - token expected
4 Halted 0 ms 0 KB -