Hackerrank New Year Chaos

HackerrankNewYearChaos.c

1 2 3  4  5 6 7 8 ; Indices
1 2 3  4  5 6 7 8 ; person-numbers
0 0 0  0  0 0 0 0 ; person-numbers - indices
0 0 0  0  0 0 0 0 ; accumulated difference
; sum of accumulated difference: 0
; Total bribery: 0
  
1 2 3  4  5 6 7 8 ; Indices
1 2 3  5  4 6 7 8 ; person-numbers
0 0 0  1 -1 0 0 0 ; person-numbers - indices
0 0 0  1  0 0 0 0 ; accumulated difference
; sum of accumulated difference: 1
; Total bribery: 1

1 2 3  4  5 6 7 8 ; Indices
1 2 5  3  4 6 7 8 ; person-numbers
0 0 2 -1 -1 0 0 0 ; person-numbers - indices
0 0 2  1  0 0 0 0 ; accumulated difference
; sum of accumulated difference: 3
; Total bribery: 2
  
1 2 3  4  5 6  7 8 ; Indices
1 2 5  3  4 7  6 8 ; person-numbers
0 0 2 -1 -1 1 -1 0 ; person-numbers - indices
0 0 2  1  0 1  0 0 ; accumulated difference
; sum of accumulated difference: 4
; Total bribery: 3

1 2 3  4 5  6  7 8 ; Indices
1 2 5  3 7  4  6 8 ; person-numbers
0 0 2 -1 2 -2 -1 0 ; person-numbers - indices
0 0 2  1 3  1  0 0 ; accumulated difference
; sum of accumulated difference: 7
; Total bribery: 4
  
1 2 3  4 5  6  7  8 ; Indices
1 2 5  3 7  4  8  6 ; person-numbers
0 0 2 -1 2 -2  1 -2 ; person-numbers - indices
0 0 2  1 3  1  2  0 ; accumulated difference
; sum of accumulated difference: 9
; Total bribery: 5

1 2 3  4 5 6  7  8 ; Indices
1 2 5  3 7 8  4  6 ; person-numbers
0 0 2 -1 2 2 -3 -2 ; person-numbers - indices
0 0 2  1 3 5  2  0 ; accumulated difference
; sum of accumulated difference: 13
; Total bribery: 6

1 2 3  4 5 6  7  8 ; Indices
1 2 5  3 7 8  6  4 ; person-numbers
0 0 2 -1 2 2 -1 -4 ; person-numbers - indices
0 0 2  1 3 5  4  0 ; accumulated difference
; sum of accumulated difference: 15
; Total bribery: 7

Since the question only asks the number of bribes, there's no need to really do a sorting, nor element swapping, nor "bubbling up" an element. All you need to do is to count the number of people who overtake a person.

void calc(vector<int> q)
{
    int ans = 0;
    for (int i = q.size() - 1; i >= 0; i--) {
        if (q[i] - (i + 1) > 2) {
            cout << "Too chaotic" << endl;
            return;
        }
        for (int j = max(0, q[i] - 2); j < i; j++)
            if (q[j] > q[i]) ans++;
    }
    cout << ans << endl;
}

0 1 2 3 4 5 6 7 ; Indices
1 2 3 4 5 6 7 8 ; before change
1 2 5 3 7 8 6 4 ; person-numbers
; Total bribery: 7