Judge correctness

#include <vector>
#include <iostream>
#include <string>



using namespace std;

int getnum(char c) {
	if (c >= 'A' && c <= 'Z') return c - 'A';
	if (c >= 'a' && c <= 'z') return c - 'a' + 26;
	if (c >= '0' && c <= '9') return c - '0' + 52;
	if (c == '+') return 62;
	return 63;
}



bool test(vector<vector<char>> & m, vector<vector<char>> & m_t, vector<vector<char>> & ans, vector<int> & r) {
	int n = m.size();
	vector<long long> check1(n);
	vector<long long> check2(n);
	for (int row = 0; row < n; row++) {
		for (int col = 0; col < n; col++) {
			check1[row] += r[col]*m_t[row][col];
		}
		check1[row] %= 64;
	}
	vector<long long> tmpr = check1;
	for (int row = 0; row < n; row++) {
		check1[row] = 0;
		for (int col = 0; col < n; col++) {
			check1[row] += tmpr[col]*m[row][col];
		}
		check1[row] %= 64;
	}

	for (int row = 0; row < n; row++) {
		for (int col = 0; col < n; col++) {
			check2[row] += r[col]*ans[row][col];
		}
		check2[row] %= 64;
	}
	return check1 == check2;

}



int main() {
	int t; cin >> t;
	while (t--) {
		int n; cin >> n;
		vector<vector<char>> m(n);
		vector<vector<char>> ans(n);
		int ntmp = n;
		int idx = 0;
		while (ntmp--) {
			string s; cin >> s;
			for (auto c : s) {
				m[idx].push_back(getnum(c));
			}
			idx++;
		}
		
		ntmp = n;
		idx = 0;
		while (ntmp--) {
			string s; cin >> s;
			for (auto c : s) {
				ans[idx].push_back(getnum(c));
			}
			idx++;
		}
		
		vector<vector<char>> m_t(n, vector<char>(n));
		for (int row = 0; row < n; row++) {
			for (int col = 0; col < n; col++) {
				m_t[col][row] = m[row][col];
			}
		}
		bool printed = false;
		for (int testn = 0; testn < 5; testn++) {
			vector<int> r(n);
			for (int i = 0; i < n; i++) {
				r[i] = rand() % 64;
			}
			if (!test(m, m_t, ans, r)) {
				cout << "0" << "\n";
				printed = true;
				break;
			}
		}
		if (!printed) cout << "1" << "\n";
	}
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: TIME LIMIT EXCEEDED

Test 5

Verdict: TIME LIMIT EXCEEDED

Test 6

Verdict: TIME LIMIT EXCEEDED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: TIME LIMIT EXCEEDED