Given are $N integers A_1,\ldots,A_N$.
Find the sum of $A_i \times A_j$ over all pairs (i,j) such that $1\leq i < j \leq N, modulo (10^9+7)$.

-----Constraints-----
- $2 \leq N \leq 2\times 10^5$
- $0 \leq A_i \leq 10^9$
- All values in input are integers.

-----Input-----
Input is given from Standard Input in the following format:
N
$A_1 \ldots A_N$

-----Output-----
Print $\sum_{i=1}^{N-1}\sum_{j=i+1}^{N} A_i A_j, modulo (10^9+7)$.

-----Sample Input-----
3
1 2 3

-----Sample Output-----
11

We have $1 \times 2 + 1 \times 3 + 2 \times 3 = 11$.

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