Problem Statement
In Takahashi's mind, there is always an integer sequence of length $2 \times 10^9 + 1$: $A = (A_{-10^9}, A_{-10^9 + 1}, ..., A_{10^9 - 1}, A_{10^9})$ and an integer $P$.
Initially, all the elements in the sequence $A$ in Takahashi's mind are $0$, and the value of the integer $P$ is $0$.
When Takahashi eats symbols +, -, > and <, the sequence $A$ and the integer $P$ will change as follows:
- When he eats
+, the value of$A_P$increases by$1$; - When he eats
-, the value of$A_P$decreases by$1$; - When he eats
>, the value of$P$increases by$1$; - When he eats
<, the value of$P$decreases by$1$.
Takahashi has a string $S$ of length $N$. Each character in $S$ is one of the symbols +, -, > and <. He chose a pair of integers $(i, j)$ such that $1 \leq i \leq j \leq N$ and ate the symbols that are the $i$-th, $(i+1)$-th, $...$, $j$-th characters in $S$, in this order. We heard that, after he finished eating, the sequence $A$ became the same as if he had eaten all the symbols in $S$ from first to last. How many such possible pairs $(i, j)$ are there?
Constraints
$1 \leq N \leq 250000$$|S| = N$- Each character in
$S$is+,-,>or<.
Input
Input is given from Standard Input in the following format:
N
S
Output
Print the answer.
样例
5
+>+<-
3
5
+>+-<
5
48
-+><<><><><>>>+-<<>->>><<><<-+<>><+<<>+><-+->><<
475
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