Submission #20141653

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Source Code Expand

#include <atcoder/all>
using namespace atcoder;
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const double pi = 3.14159265359;
const ll INF = 1LL << 60;

int main()
{
  int n;
  cin >> n;

  vector<ll> a(n);
  ll maxa = -10000000;
  ll mina =  10000000;
  int imax = -1, imin = -1;
  for (int i = 0; i < n; i++){
    cin >> a[i];
    if (a[i] > maxa){
      maxa = a[i];
      imax = i;
    }
    if (a[i] < mina){
      mina = a[i];
      imin = i;
    }
  }

  vector<pair<int, int>> ans;
  bool allPositive = true;

  if (mina >= 0){
    allPositive = true;
  } else if (maxa <= 0){
    allPositive = false;
  } else {
    if (abs(maxa) >= abs(mina)){
      allPositive = true;
      for (int i = 0; i < n; i++){
	ans.push_back(make_pair(imax+1, i+1));
      }
    } else {
      allPositive = false;
      for (int i = 0; i < n; i++){
	ans.push_back(make_pair(imin+1, i+1));
      }
    }
  }

  if (allPositive){
    for (int i = 1; i < n; i++)
      ans.push_back(make_pair(i, i+1));
  } else {
    for (int i = n; i > 1; i--)
      ans.push_back(make_pair(i, i-1));
  }
	
  cout << ans.size() << endl;
  for (auto p : ans){
    cout << p.first << " " << p.second << endl;
  }
  return 0;
}

Submission Info

Judge Result