3SUM

#include <algorithm>
#include <iostream>
#include <queue>
#include <vector>

using namespace std;

bool find3Numbers(vector<int>& arr, int sum) 
{
    int n = arr.size();
    
    for (int i = 0; i < n - 2; i++)
    { 
        for (int j = i + 1; j < n - 1; j++)
        { 

            for (int k = j + 1; k < n; k++)
            { 
                if (arr[i] + arr[j] + arr[k] == sum)
                { 
                    cout << i + 1 << ' ' << j + 1<< ' ' << k + 1 << endl; 
                    return true; 
                } 
            } 
        } 
    }
    cout << "IMPOSSIBLE" << endl;
    return false; 
} 


int main() 
{ 
    int n, t;
    cin >> n >> t;
    vector<int> arr(n);
    for (int i = 0; i < n; i++)
    {
        cin >> arr[i];
    }
    
    find3Numbers(arr, t); 
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: TIME LIMIT EXCEEDED

Test 11

Verdict: TIME LIMIT EXCEEDED

Test 12

Verdict: TIME LIMIT EXCEEDED

Test 13

Verdict: TIME LIMIT EXCEEDED

Test 14

Verdict: TIME LIMIT EXCEEDED

Test 15

Verdict: TIME LIMIT EXCEEDED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: TIME LIMIT EXCEEDED

Test 19

Verdict: TIME LIMIT EXCEEDED

Test 20

Verdict: TIME LIMIT EXCEEDED

Test 21

Verdict: TIME LIMIT EXCEEDED

Test 22

Verdict: TIME LIMIT EXCEEDED

Test 23

Verdict: ACCEPTED