重新发一个

#include <bits/stdc++.h>
using namespace std;

int gcd(int a, int b) {
	if (b == 0)return a;
	return gcd(b, a % b);
}

int main() {
	int t;
	cin >> t;
	while (t--) {
	int n;
	cin >> n;
	int a[1010] = {0};
	for (int i = 1; i <= n; i++) {
		int x;
		cin >> x;
		a[x] = i;
	}
	int cnt = -1;
	for (int i = 1; i <= 1000; i++) {
	     for (int j = i; j <= 1000; j++) {
		if (a[i] != 0 && a[j] != 0 && a[i] + a[j] > cnt && gcd(i, j) == 1) {
			cnt = a[i] + a[j];
		}
	      }
	}
	cout << cnt << endl;
	}
	return 0;
}