Submission #950481

#	Time	Username	Problem	Language	Result	Execution time	Memory
950481		andrei_boaca	Chorus (JOI23_chorus)	C++17	40 / 100	7018 ms	59964 KiB

chorus

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
const ll INF=1e17;
ll n,k,lga,lgb,makegood;
ll A[1000005],B[1000005];
ll dp[5005][5005];
string str;
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>k;
    cin>>str;
    for(int i=0;i<str.size();i++)
    {
        if(str[i]=='A')
            A[++lga]=i+1;
        else
            B[++lgb]=i+1;
    }
    for(int i=1;i<=n;i++)
        if(A[i]>B[i])
        {
            ll x=A[i];
            A[i]=B[i];
            for(int j=i;j<=n;j++)
            {
                if(B[j]<x)
                {
                    B[j]++;
                    makegood++;
                }
                else
                    break;
            }
        }
    for(int i=n;i>=1;i--)
    {
        dp[i][0]=INF;
        for(int cnt=1;cnt<=k;cnt++)
        {
            ll suma=0;
            ll cost=0;
            int ind=i;
            dp[i][cnt]=dp[i+1][cnt-1];
            for(int j=i+1;j<=n;j++)
            {
                while(ind<=n&&B[ind]<A[j])
                {
                    suma++;
                    ind++;
                }
                cost+=suma;
                dp[i][cnt]=min(dp[i][cnt],cost+dp[j+1][cnt-1]);
            }
        }
    }
    cout<<dp[1][k]+makegood;
    return 0;
}

Compilation message (stderr)

chorus.cpp: In function 'int main()':
chorus.cpp:16:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |     for(int i=0;i<str.size();i++)
      |                 ~^~~~~~~~~~~

• Subtask 1: 16 / 16
• Subtask 2: 24 / 24
• Subtask 3: 0 / 21
• Subtask 4: 0 / 26
• Subtask 5: 0 / 13