Järjestäminen

input/code.cpp: In function 'int main()':
input/code.cpp:40:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0; i < ve.size(); i++){
                  ~~^~~~~~~~~~~
input/code.cpp:41:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int j = i+1; j < ve.size(); j++){
                     ~~^~~~~~~~~~~

#include<bits/stdc++.h>
using namespace std;

int main(){
	int t;
	cin >> t;
	while(t--){
		int n;
		cin >> n;
		vector<int> ve = {};
		for(int i = 0; i < n; i++){
			int a;
			cin >> a;
			ve.push_back(a);
		}
		if(n == 1){
			cout << "YES\n";
			continue;
		}
		if(n == 2){
	//		cout << "TÄLK\n";
			if(ve[0] == 1 && ve[1] == 2) cout << "YES\n";
			else cout << "NO\n";
			continue;
		}
		if(n == 3){
			if(ve[0] == 1 && ve[1] == 2 && ve[2] == 3) cout << "YES\n";
			else cout << "NO\n";
			continue;
		}
		if(n == 4){
			if((ve[0] == 1 && ve[1] == 2 && ve[2] == 3 && ve[3] == 4) || (ve[0] == 3 && ve[1] == 4 && ve[2] == 1 && ve[3] == 2)){
				cout << "YES\n";
			}else{
				cout << "NO\n";
			}
			continue;
		}
		int su = 0;
		for(int i = 0; i < ve.size(); i++){
			for(int j = i+1; j < ve.size(); j++){
				if(ve[i] > ve[j]) su++;
			}
		}
		if(su % 2 == 0) cout << "YES\n";
		else cout << "NO\n";
	}
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 1, 2

Verdict: ACCEPTED