SWAPPALI Subtask1

During contest, i tried to get subtask 1 corrected, but its giving WA. any suggestions?

here is my code -

ll test;
cin >> test;
while (test–)
{

	ll n, temp, c;
	ll verdict = 0;
	string s, t;

	cin >> n;
	cin >> t;

	for (int j = 0; j < n; ++j)
	{
		if (t[j] == t[t.size() - j - 1])
		{
			if (j == n - 1)
			{
				verdict = -1;
			}
			continue;
		}
		else
		{
			break;
		}
	}
	if (verdict != -1)
	{
		for (ll i = 0; i < n - 1; ++i)
		{
			s = t;
			temp = s[i];
			s[i] = s[i + 1];
			s[i + 1] = temp;

			for (ll j = 0; j < n; ++j)
			{
				if (s[j] == s[s.size() - j - 1])
				{
					if (j == n - 1)
						verdict = 1;
					continue;
				}
				else
				{
					break;
				}

			}
		}
	}

	if (verdict == -1)
		cout << "YES\n0\n";
	else
		verdict == 1 ?
		cout << "YES\n1\n" :
		     cout << "NO\n";
}