Question

Spell Splice

1

2

1 10

5 5

55

Gaurav has N magic spells. The i^{th} spell has a volatility of V_{i} and a strength of A_{i}. When spells i and j (1 ≤ i < j ≤ N) are activated together, they merge to form a single spell of strength (A_{i }× V_{j }+ V_{i} × A_{j}).

What's the **maximum** possible strength of a spell Chef can obtain by activating exactly two of his spells?

Input

The first line of input will contain a single integer T, denoting the number of test cases.

Each test case consists of multiple lines of input.

The first line of each test case contains a single integer N, the number of spells.

The next N lines describe the spells. The i

1 ≤ T ≤ 10

2 ≤ N ≤ 100

1 ≤ A

Each test case consists of multiple lines of input.

The first line of each test case contains a single integer N, the number of spells.

The next N lines describe the spells. The i

^{th}of them contains two space-separated integers V_{i}and A_{i}- the volatility and strength of the i^{th}spell.**Constraints**1 ≤ T ≤ 10

^{2}2 ≤ N ≤ 100

1 ≤ A

_{i}, V_{i}≤ 1000Output

For each test case, output on a new line the maximum possible power of a combined spell.

Example

**Sample Input**

1

2

1 10

5 5

**Sample Output**

55

**Explanation**

**Test case 1**There are only two spells. Combining them results in a spell of strength of 1×5 + 5×10 = 55.