提出 #50123787

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ソースコード 拡げる

#include<bits/stdc++.h>

using namespace std;

int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  int n,k;
  cin >> n >> k;
  if(n%2==0){cout << "-1\n";return 0;}

  int g=gcd(n,k);
  vector<vector<int>> v(g,vector<int>(n/g));
  for(int i=0;i<g;i++){
    int x=i;
    for(int j=0;j<(n/g);j++){
      v[i][j]=x;
      x+=k;x%=n;
    }
  }

  vector<pair<int,int>> res;
  for(int i=0;i<v[0].size()-1;i+=2){
    res.push_back({v[0][i],v[0][i+1]});
  }
  for(int i=1;i<g;i++){
    for(int j=3;j<v[0].size()-1;j+=2){
      res.push_back({v[i-1][j],v[i][j]});
    }
  }
  for(int i=2;i<v.size();i+=2){
    res.push_back({v[i-2][0],v[i-1][0]});
    res.push_back({v[i-1][1],v[i][1]});
    res.push_back({v[i][0],v[i][1]});
  }

  cout << res.size() << "\n";
  for(auto &nx : res){
    cout << nx.first << " " << nx.second << "\n";
  }
  return 0;
}

提出情報

コンパイルエラー

Main.cpp: In function ‘int main()’:
Main.cpp:24:16: warning: comparison of integer expressions of different signedness: ‘int’ and ‘std::vector<int>::size_type’ {aka ‘long unsigned int’} [-Wsign-compare]
   24 |   for(int i=0;i<v[0].size()-1;i+=2){
      |               ~^~~~~~~~~~~~~~
Main.cpp:28:18: warning: comparison of integer expressions of different signedness: ‘int’ and ‘std::vector<int>::size_type’ {aka ‘long unsigned int’} [-Wsign-compare]
   28 |     for(int j=3;j<v[0].size()-1;j+=2){
      |                 ~^~~~~~~~~~~~~~
Main.cpp:32:16: warning: comparison of integer expressions of different signedness: ‘int’ and ‘std::vector<std::vector<int> >::size_type’ {aka ‘long unsigned int’} [-Wsign-compare]
   32 |   for(int i=2;i<v.size();i+=2){
      |               ~^~~~~~~~~

ジャッジ結果