3SUM

import sys

def main():
    input = sys.stdin.read
    data = input().split()

    n = int(data[0])
    x = int(data[1])
    a = []
    for i in range(n):
        a.append((int(data[2 + i]), i + 1))
        
    a.sort(key=lambda item: item[0])

    for i in range(n - 2):
        left = i + 1
        right = n - 1
        
        while left < right:
            sum_curr = a[i][0] + a[left][0] + a[right][0]
            
            if sum_curr == x:
                print(f"{a[i][1]} {a[left][1]} {a[right][1]}")
                return
            elif sum_curr < x:
                left += 1
            else:
                right -= 1            
    print("IMPOSSIBLE")
#sort then move pointers

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER

Test 11

Verdict: WRONG ANSWER

Test 12

Verdict: WRONG ANSWER

Test 13

Verdict: WRONG ANSWER

Test 14

Verdict: WRONG ANSWER

Test 15

Verdict: WRONG ANSWER

Test 16

Verdict: WRONG ANSWER

Test 17

Verdict: WRONG ANSWER

Test 18

Verdict: WRONG ANSWER

Test 19

Verdict: WRONG ANSWER

Test 20

Verdict: WRONG ANSWER

Test 21

Verdict: WRONG ANSWER

Test 22

Verdict: WRONG ANSWER

Test 23

Verdict: WRONG ANSWER