description: Vupsen and Pupsen were gifted an integer array. Since Vupsen doesn't like the number 0, he threw away all numbers equal to 0 from the array. As a result, he got an array a of length n.
  
  Pupsen, on the contrary, likes the number 0 and he got upset when he saw the array without zeroes. To cheer Pupsen up, Vupsen decided to come up with another array b of length n such that ∑_{i=1}^{n}a_i ⋅ b_i=0. Since Vupsen doesn't like number 0, the array b must not contain numbers equal to 0. Also, the numbers in that array must not be huge, so the sum of their absolute values cannot exceed 10^9. Please help Vupsen to find any such array b!
  
  Input
  
  The first line contains a single integer t (1 ≤ t ≤ 100) — the number of test cases. The next 2 ⋅ t lines contain the description of test cases. The description of each test case consists of two lines.
  
  The first line of each test case contains a single integer n (2 ≤ n ≤ 10^5) — the length of the array.
  
  The second line contains n integers a_1, a_2, …, a_n (-10^4 ≤ a_i ≤ 10^4, a_i ≠ 0) — the elements of the array a.
  
  It is guaranteed that the sum of n over all test cases does not exceed 2 ⋅ 10^5.
  
  Output
  
  For each test case print n integers b_1, b_2, …, b_n — elements of the array b (|b_1|+|b_2|+… +|b_n| ≤ 10^9, b_i ≠ 0, ∑_{i=1}^{n}a_i ⋅ b_i=0).
  
  It can be shown that the answer always exists.
  
  Example
  
  Input
  
  
  3
  2
  5 5
  5
  5 -2 10 -9 4
  7
  1 2 3 4 5 6 7
  
  
  Output
  
  
  1 -1
  -1 5 1 -1 -1
  -10 2 2 -3 5 -1 -1
  
  Note
  
  In the first test case, 5 ⋅ 1 + 5 ⋅ (-1)=5-5=0. You could also print 3 -3, for example, since 5 ⋅ 3 + 5 ⋅ (-3)=15-15=0
  
  In the second test case, 5 ⋅ (-1) + (-2) ⋅ 5 + 10 ⋅ 1 + (-9) ⋅ (-1) + 4 ⋅ (-1)=-5-10+10+9-4=0.
solution: /*==========================================================================
  *   	AUTHOR:    RonWonWon
  *   	CREATED:   24.10.2021 17:30:32        
  /*==========================================================================*/
  import java.io.*;
  import java.util.*;
  
  public class D {
  	
  	public static void main(String[] args) throws IOException {
  		/*
      in.ini();
      PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("output.txt")));
      */
      long startTime = System.nanoTime();
      int t = in.nextInt(), T = 1;  
      while(t-->0) { 
        int n = in.nextInt();
        int a[] = in.readArray(n);
        Pair b[] = new Pair[n];
        for(int i=0;i<n;i++) b[i] = new Pair(i,Math.abs(a[i])); 
        Arrays.sort(b);
        int ans[] = new int[n];
        int i = n-1;
        while(i>-1){
        	Pair v1 = b[i];
        	if(i-1==1){
        		Pair v2 = b[i-1], v3 = b[i-2];
        		int id1 = v1.x, id2 = v2.x, id3 = v3.x;
        		if(a[id1]<0) ans[id1] = (-(v2.y+v3.y));
        		else ans[id1] = ((v2.y+v3.y));
        		if(a[id2]>0) ans[id2] = (-v1.y);
        		else ans[id2] = (v1.y);
        		if(a[id3]>0) ans[id3] = (-v1.y);
        		else ans[id3] = (v1.y);
        		break;
        	}
        	else{
        		Pair v2 = b[i-1];
        		int id1 = v1.x, id2 = v2.x;
        		if(a[id1]<0) ans[id1] = (-v2.y);
        		else ans[id1] = (v2.y);
        		if(a[id2]>0) ans[id2] = (-v1.y);
        		else ans[id2] = (v1.y);
        		i-=2;
        	}
        }
        for(int ii : ans) out.print(ii+" ");
        out.println();
     		//out.println("Case #"+T+": "+ans); T++;
      }
      /*
      startTime = System.nanoTime() - startTime;
      System.err.println("Time: "+(startTime/1000000));
      */
      out.flush();
  	}
  	
  	static class Pair implements Comparable<Pair> {
  		int x, y;
  		Pair(int a, int b){ x = a; y = b; }		
  		@Override
  		public int compareTo(Pair o) {
  			return y - o.y;
  		}
  	}
  	
  	static FastScanner in = new FastScanner();
    static PrintWriter out = new PrintWriter(System.out);
  	static int oo = Integer.MAX_VALUE;
  	static long ooo = Long.MAX_VALUE;
  	
  	static class FastScanner {
  		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  		StringTokenizer st = new StringTokenizer("");
  		
  		void ini() throws FileNotFoundException {
  			br = new BufferedReader(new FileReader("input.txt"));
  		}
  		
  		String next() {
  			while(!st.hasMoreTokens())
  				try { st = new StringTokenizer(br.readLine()); }
  				catch(IOException e) {}
  			return st.nextToken();
  		}
  		
  		String nextLine(){
  			try{ return br.readLine(); } 
  			catch(IOException e) { } return "";
  		}
  		
  		int nextInt() {
  			return Integer.parseInt(next());
  		}
  		
  		int[] readArray(int n) {
  			int a[] = new int[n];
  			for(int i=0;i<n;i++) a[i] = nextInt();
  			return a;
  		}
  		
  		long nextLong() {
  			return Long.parseLong(next());
  		}
  		
  		long[] readArrayL(int n) {
  			long a[] = new long[n];
  			for(int i=0;i<n;i++) a[i] = nextLong();
  			return a;
  		}
  		
  		double nextDouble() {
  			return Double.parseDouble(next());
  		}
  		
  		double[] readArrayD(int n) {
  			double a[] = new double[n];
  			for(int i=0;i<n;i++) a[i] = nextDouble();
  			return a;
  		}
  	}
  
  	static final Random random = new Random();
  
  	static void ruffleSort(int[] a){
  		int n = a.length;
  		for(int i=0;i<n;i++){
  			int j = random.nextInt(n), temp = a[j];
  			a[j] = a[i]; a[i] = temp;
  		}
  		Arrays.sort(a); 	
  	}
  	
  	static void ruffleSortL(long[] a){
  		int n = a.length;
  		for(int i=0;i<n;i++){
  			int j = random.nextInt(n);
  			long temp = a[j];
  			a[j] = a[i]; a[i] = temp;
  		}
  		Arrays.sort(a); 	
  	}
  }
  