Partial sums P70578

Given an array $A[0 ~..~ n-1]$ and an index $i$, the $i$-th partial sum of $A$ is $\sum_{0\le j\le i} A[j]$. Here, you have to implement a data structure to efficiently compute partial sums. The operations you must consider are the creation of an array with all its values initialized to zero, the modification of a value, and the query of a partial sum.

Input

Input consists of a non-empty sequence of commands. Every command begins with a letter to identify it, followed by one or two integer-number parameters. These are the possible commands:

• “r $n$” resets (or creates) an array of $n$ integer numbers to zero. Assume $1 \le n \le 10^5$.

• “s $i$ $x$” sets the possition $i$ to $x$. Assume $0\le i< n$ and $-100\le x\le 100$.

• “g $i$” gets (and prints) the $i$-th partial sum. Assume $0\le i< n$.

In general, there are much more set and get commands than reset commands. The first command is always a reset.

Output

For each get command, print the corresponding partial sum. Print the output corresponding to each reset command on a unique line, separated by spaces.