You are given a permutation of the integers from to . You want to find
In other words, let . You want to find the sum of for all .
Input Specification
The first line will contain the integer .
The next line will contain space-separated integers, . is guaranteed to be pairwise distinct. In other words, forms a permutation.
Output Specification
The answer to the problem. Note that the answer may not fit in a 32-bit integer.
Sample Input 1
3
2 1 3
Sample Output 1
9
Sample Input 2
4
1 3 2 4
Sample Output 2
19
Sample Input 3
8
5 4 8 1 2 6 7 3
Sample Output 3
85
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