Submission #1156609

#	Time	Username	Problem	Language	Result	Execution time	Memory
1156609		the_ZHER	Martian DNA (BOI18_dna)	C++20	0 / 100	48 ms	3252 KiB

dna

#include <bits/stdc++.h>
#define boost ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define int long long
using namespace std;
const int inf=1e17;
const int N=2e5+5;
const int N1=1e5+5;
const int N2=5e6+6;
const int mod=1e9+7;
const int k1=447;
struct edge{
    int d,in;
};
struct edge1{
    int l,r;
};
vector<int>v;
int dp[N];
int dp1[N];
signed main(){
    int n,k,q;
    cin>>n>>k>>q;
    v.push_back(0);
    for(int i=1;i<=n;i++){
        int x;
        cin>>x;
        dp[x]++;
        v.push_back(x);
    }
    int ok=0;
    for(int i=1;i<=q;i++){
        int x,cnt;
        cin>>x>>cnt;
        dp1[x]=max(dp1[x],cnt);
        if(dp[x]<cnt){
            ok=1;
        }
    }
    if(ok==1){
        cout<<"impossible";
        return 0;
    }
    int l=1,r=n;
    int ans=n;
    while(l<r){
        int ok1=0;
        if(dp[v[l]]-1>=dp1[v[l]]){
            dp[v[l]]--;
            l++;
            ok1=1;
        }
        if(dp[v[r]]-1>=dp1[v[r]]){
            dp[v[r]]--;
            r--;
            ok1=1;
        }
        if(ok1==0){
            break;
        }
    }
    cout<<r-l+1;
}  

• Subtask 1: 0 / 16
• Subtask 2: 0 / 24
• Subtask 3: 0 / 28
• Subtask 4: 0 / 32