제출 #628524

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
628524		Sorting	수천개의 섬 (IOI22_islands)	C++17	컴파일 에러	0 ms	0 KiB

islands

#include "islands.h"

#include <variant>
#include <vector>
#include <algorithm>
#include <cmath>

using namespace std;

std::variant<bool, std::vector<int>> find_journey(
    int n, int m, std::vector<int> u, std::vector<int> v) {
    if(n == 2){
        vector<int> cnt[2]{};
        for(int i = 0; i < u.size();++i){
            cnt[u[i]].push_back(i);
        }
        
        if(cnt[0].size() >= 2 && cnt[1].size() >= 1){
            return vector<int>{cnt[0][0], cnt[1][0], cnt[0][1], cnt[0][0], cnt[1][0], cnt[0][1]};
        }
        return false;
    }
    vector<vector<pair<int, int>>> adj(n);
    for(int i = 0; i < m; ++i)
        adj[u[i]].push_back({v[i], i});
    
    int x = 1, par = -1;
    while(true){
        if(adj[x].size() != 1 + (x != 1)){
            if(adj[x].size() < 1 + (x != 1)){
                return false;
            }
            return true;
        }
        for(auto p: adj[x]){
            int to = p.first;
            int idx = p.second;
            if(to == par){
                par = -1;
                continue;
            }
            par = x;
            x = to;
        }
    }
    assert(false);
}

컴파일 시 표준 에러 (stderr) 메시지

islands.cpp: In function 'std::variant<bool, std::vector<int, std::allocator<int> > > find_journey(int, int, std::vector<int>, std::vector<int>)':
islands.cpp:14:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |         for(int i = 0; i < u.size();++i){
      |                        ~~^~~~~~~~~~
islands.cpp:37:17: warning: unused variable 'idx' [-Wunused-variable]
   37 |             int idx = p.second;
      |                 ^~~
islands.cpp:46:5: error: 'assert' was not declared in this scope
   46 |     assert(false);
      |     ^~~~~~
islands.cpp:7:1: note: 'assert' is defined in header '<cassert>'; did you forget to '#include <cassert>'?
    6 | #include <cmath>
  +++ |+#include <cassert>
    7 |