제출 #1356546

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1356546		free_de_la_zenith	Monochrome Points (JOI20_monochrome)	C++20	100 / 100	10 ms	2520 KiB

monochrome

/**
 *    author:  MINHTPC
 *
**/
#include <bits/stdc++.h>

#define ll long long
#define fi first
#define se second
#define pb push_back
#define all(a) a.begin() , a.end()
#define FOR(i ,a , b) for(int i = a ; i <= b ; ++i)
#define bit(mask,i) ((mask>>i)&1)
#define name "task"
#define lo lower_bound
#define up upper_bound
#define count_bit1(x) __builtin_popcountll(x)
#define count_bit01(x) __builtin_clzll(x)
#define count_bit10(x) __builtin_ctzll(x)

using namespace std;
const int N=6e5+5;
string s;
int pre[N];
int n;
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    if(fopen("umnik.inp","r")) {
        freopen("umnik.inp","r",stdin);
    }
    cin >> n;
    cin >> s;
    for(int i=0;i<2*n;i++) {
        if(s[i]=='B') pre[i]+=1;
        else {
            int ni=(i+n)%(2*n);
            pre[ni]--;
        }
    }
    for(int i=1;i<2*n;i++) pre[i]+=pre[i-1];
    sort(pre,pre+2*n);
    int med=pre[n-1];
    ll ans=1LL*n*(n-1);
    for(int i=0;i<2*n;i++) ans-=abs(med-pre[i]);
    cout << ans/2;
}

컴파일 시 표준 에러 (stderr) 메시지

monochrome.cpp: In function 'int main()':
monochrome.cpp:31:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |         freopen("umnik.inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 21 / 21
• Subtask 3: 10 / 10
• Subtask 4: 65 / 65