Submission #378705

#	Time	Username	Problem	Language	Result	Execution time	Memory
378705		8e7	Gift (IZhO18_nicegift)	C++14	18 / 100	654 ms	524292 KiB

nicegift

//Challenge: Accepted
#include <iostream>
#include <algorithm>
#include <vector>
#include <utility>
#include <queue>
#define ll long long
#define maxn 1000005
#define pii pair<int, ll>
#define ff first
#define ss second
#define io ios_base::sync_with_stdio(0);cin.tie(0);
using namespace std;
ll a[maxn];
vector<int> val;
int main() {
	io
	ll n, k;
	cin >> n >> k;
	for (int i = 0;i < n;i++) {
		cin >> a[i];
		for (int j = 0;j < a[i];j++) {
			val.push_back(i);
		}
	}
	bool poss = val.size() % 2 == 0;
	for (int i = 0;i < val.size() / 2;i++) {
		if (val[i] == val[i + val.size() / 2]) {
			poss = false;
			break;
		}
	}
	if (!poss) {
		cout << -1 << endl;
	} else {
		cout << val.size() / 2 << "\n";
		for (int i = 0;i < val.size() / 2;i++) {
			cout << 1 << " " << val[i]+1 << " " << val[i + val.size() / 2]+1 << "\n";
		}
	}
}

Compilation message (stderr)

nicegift.cpp: In function 'int main()':
nicegift.cpp:27:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |  for (int i = 0;i < val.size() / 2;i++) {
      |                 ~~^~~~~~~~~~~~~~~~
nicegift.cpp:37:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |   for (int i = 0;i < val.size() / 2;i++) {
      |                  ~~^~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 11 / 11
• Subtask 3: 0 / 12
• Subtask 4: 0 / 19
• Subtask 5: 0 / 51