oj.uz

Submission #984547

# Submission time Handle Problem Language Result Execution time Memory
984547 2024-05-16T18:34:53 Z Ahmed57 Alternating Current (BOI18_alternating) C++17
19 / 100
 3000 ms 10756 KB 
#include <bits/stdc++.h>

using namespace std;
#define int long long

signed main(){
    ios_base::sync_with_stdio(false);cin.tie(0);
    int n,m;cin>>n>>m;
    int pref[n+2] = {0};
    vector<array<int,3>> v;
    vector<array<int,2>> rng[n+1];
    int dir[m+1] = {0};
    int ma = -1, lol = -1;
    for(int i = 0;i<m;i++){
        int a,b;cin>>a>>b;
        if(a<=b){
            pref[a]++;
            pref[b+1]--;
        }else{
            pref[a]++;
            pref[1]++;
            pref[b+1]--;
            b+=n;
        }
        v.push_back({a,b,i});
        rng[a].push_back({b,i});
        if(a==1){
            if(b>ma){
                ma = b;
                lol = i;
            }
        }
    }    
    for(int i = 2;i<=n;i++){
        pref[i]+=pref[i-1];
    }
    for(int i = 1;i<=n;i++){
        if(pref[i]<=1){
            cout<<"impossible\n";
            return 0;
        }
    }
    for(int i = (max(n,m)<=1000?0:lol);i<(max(n,m)<=1000?m:lol+1);i++){
        for(int j = 0;j<m;j++)dir[j] = 0;
        int ind = v[i][0];
        int nah = v[i][1], fe = v[i][2];
        bool bad = 0;
        while(ind<v[i][0]+n){
            if(ind-1==nah){
                bad = 1;
                break;
            }
            if(nah==-1){
                bad = 1;
                break;
            }
            int er = nah;
            dir[fe] = 1;
            if(er>=v[i][0]+n){
                break;
            }
            while(ind<=er){
                ind++;
                for(auto j:rng[(ind-1)%n+1]){
                    if(nah<(j[0]>n?j[0]:(ind<=n?j[0]:j[0]+n))){
                        nah = (j[0]>n?j[0]:(ind<=n?j[0]:j[0]+n));
                        fe = j[1];
                    }
                }
                if(ind<=er&&pref[(ind-1)%n+1]==2)nah = -1;
            }
        }
        int npref[n+2];
        for(int j = 1;j<=n;j++){
            npref[j] = 0;
        }
        for(int j = 0;j<m;j++){
            if(dir[j])continue;
            if(v[j][1]>n){
                npref[v[j][0]]++;
                npref[1]++;
                npref[(v[j][1]-1)%n+2]--;
            }else{
                npref[v[j][0]]++;
                npref[v[j][1]+1]--;
            }
        }
        for(int j = 2;j<=n;j++)npref[j]+=npref[j-1];
        for(int j = 1;j<=n;j++){
            if(npref[j]==0){
                bad = 1;
                break;
            }
        }
        if(bad==0){
            for(int j = 0;j<m;j++){
                cout<<dir[j];
            }
            return 0;
        }
    }
    cout<<"impossible\n";
}

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Execution timed out 3069 ms 348 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Execution timed out 3069 ms 348 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Execution timed out 3069 ms 348 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 9180 KB Output is correct
2 Correct 4 ms 4188 KB Output is correct
3 Correct 13 ms 6628 KB Output is correct
4 Correct 17 ms 7440 KB Output is correct
5 Correct 27 ms 9996 KB Output is correct
6 Correct 22 ms 9232 KB Output is correct
7 Correct 27 ms 9728 KB Output is correct
8 Correct 4 ms 4440 KB Output is correct
9 Correct 3 ms 4184 KB Output is correct
10 Correct 36 ms 10756 KB Output is correct
11 Correct 22 ms 10508 KB Output is correct
12 Correct 24 ms 9996 KB Output is correct
13 Correct 2 ms 3420 KB Output is correct
14 Correct 2 ms 3420 KB Output is correct
15 Correct 27 ms 10248 KB Output is correct
16 Correct 11 ms 6672 KB Output is correct
17 Correct 27 ms 9988 KB Output is correct
18 Correct 25 ms 6408 KB Output is correct
19 Correct 3 ms 3932 KB Output is correct
20 Correct 23 ms 7784 KB Output is correct

Subtask #5
0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Execution timed out 3069 ms 348 KB Time limit exceeded
5 Halted 0 ms 0 KB -