#include <bits/stdc++.h>   using namespace std;   long long t;   long long n;   long long tmp;   long long gcd(long long a, long long b) {     long long temp;     if (a < b) {       temp = a;       a = b;       b = temp;     }     while (b != 0) {       temp = a % b;       a = b;       b = temp;     }     return a;   }   long long lcm(long long a, long long b) {     long long temp_lcm;     temp_lcm = a * b / gcd(a, b);     return temp_lcm;   }   int main() {     cin >> t;     while (t--) {       cin >> n;       if (n % 2 == 0) {         long long a, b;         tmp = n / 2;         while (tmp--) {           cin >> a >> b;           cout << b <<     << -a <<    ;         }         cout << endl;       } else {         long long a, b, c;         tmp = (n - 2) / 2;         while (tmp--) {           cin >> a >> b;           cout << b <<     << -a <<    ;         }         cin >> a >> b >> c;         tmp = lcm(a, b);         tmp = lcm(tmp, c);         cout << tmp / a <<     << tmp / b <<     << -2 * tmp / c;         cout << endl;       }     }     return 0;   }   