제출 #1330226

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1330226		bradley0927	Grid Coloring (JOI25_ho_t1)	C++20	컴파일 에러	0 ms	0 KiB

Main

#include <iostream>
#include <vector>
#include <map>
#include <algorithm>
using namespace std;
int main(){
    int n;
    cin >> n;
    vector<int> A(n+1), B(n+1);
    for(int i=1;i<=n;i++) cin>>A[i];
    for(int j=1;j<=n;j++) cin>>B[j];
    
    // prefix maxes
    vector<int> PA(n+1), PB(n+1);
    PA[1]=A[1]; for(int i=2;i<=n;i++) PA[i]=max(PA[i-1],A[i]);
    PB[1]=B[1]; for(int j=2;j<=n;j++) PB[j]=max(PB[j-1],B[j]);
    
    // count frequency in PA and PB
    map<int,long long> cntA, cntB;
    for(int i=1;i<=n;i++) cntA[PA[i]]++;
    for(int j=1;j<=n;j++) cntB[PB[j]]++;
    
    // collect all colors
    set<int> colors;
    for(auto& [v,_]: cntA) colors.insert(v);
    for(auto& [v,_]: cntB) colors.insert(v);
    
    long long bestCount = 0;
    int bestColor = 0;
    long long cumA = 0, cumB = 0; // cumulative counts ≤ c
    
    for(int c : colors){
        long long R = cntA.count(c) ? cntA[c] : 0;
        long long C = cntB.count(c) ? cntB[c] : 0;
        cumA += R;
        cumB += C;
        // R' = cumA, C' = cumB, R_less = cumA - R, C_less = cumB - C
        long long count = R * cumB + (cumA - R) * C;
        if(count > bestCount || (count == bestCount && c > bestColor)){
            bestCount = count;
            bestColor = c;
        }
    }
    cout << bestColor << " " << bestCount << "\n";
}

컴파일 시 표준 에러 (stderr) 메시지

Main.cpp: In function 'int main()':
Main.cpp:24:5: error: 'set' was not declared in this scope
   24 |     set<int> colors;
      |     ^~~
Main.cpp:5:1: note: 'std::set' is defined in header '<set>'; did you forget to '#include <set>'?
    4 | #include <algorithm>
  +++ |+#include <set>
    5 | using namespace std;
Main.cpp:24:9: error: expected primary-expression before 'int'
   24 |     set<int> colors;
      |         ^~~
Main.cpp:25:28: error: 'colors' was not declared in this scope
   25 |     for(auto& [v,_]: cntA) colors.insert(v);
      |                            ^~~~~~
Main.cpp:26:28: error: 'colors' was not declared in this scope
   26 |     for(auto& [v,_]: cntB) colors.insert(v);
      |                            ^~~~~~
Main.cpp:32:17: error: 'colors' was not declared in this scope
   32 |     for(int c : colors){
      |                 ^~~~~~