Problem:
Range Sum Query

Write a program which manipulates a sequence A = {a1, a2, . . . , an} with the following operations:

add(i, x): add x to ai.

getSum(s, t): print the sum of as, as+1,...,at.

Note that the initial values of ai (i = 1, 2, . . . , n) are 0.

Input

n q
com1 x1 y1
com2 x2 y2
...
comq xq yq

In the first line, n (the number of elements in A) and q (the number of queries) are given. Then, q queries are given where com represents the type of queries. '0' denotes add(xi, yi) and '1' denotes getSum(xi, yi).

Output

For each getSum operation, print the sum in a line.

Constraints

1 ≤ n ≤ 100000

1 ≤ q ≤ 100000

If comi is 0, then 1 ≤ xi ≤ n, 0 ≤ yi ≤ 1000.

If comi is 1, then 1 ≤ xi ≤ n, 1 ≤ yi ≤ n.

Sample Input 1

3 5
0 1 1
0 2 2
0 3 3
1 1 2
1 2 2

Sample Output 1

3
2

Solution in JAVA (judge verdict: Runtime Error)

import java.util.Scanner;

public class Main {
	int[] a;
	int n=2;
	public static void main(String[] args){
		Main test = new Main();
		Scanner inputScanner = new Scanner(System.in).useDelimiter("\\s");
		int n1 = inputScanner.nextInt();
		int q = inputScanner.nextInt();
		
		
		while (test.n < n1){
			test.n *= 2;
		}
	//	System.out.println(Integer.toString(test.n));
		test.a = new int[(2 * test.n)-1 ]; 
	//	System.out.println(test.a.length);
		for(int i=0;i<test.a.length;i++){
			test.a[i]=0;
		}
		
		
		
		
		int cmd=-1;
		int arg1;
		int arg2;
		for(int j =0;j<q;j++){
			cmd = inputScanner.nextInt();
			arg1=inputScanner.nextInt();
			arg2=inputScanner.nextInt();
			
			if(cmd ==0)
				test.update(arg1, arg2);
			else if(cmd ==1)
				System.out.println(test.findSum(arg1, arg2));
		}
	}
	
	public void update(int k, int b){
		k += (n-2);
		a[k] += b;
		while(k > 0){
			k = (k-1)/2;
			a[k] = Integer.min(a[(k*2)+1], a[(k*2)+2]);
		}
	}
	
	public int findMin(int b, int c){
		
		return query(b,c+1,0,0,n);
	}
	
	public int query(int b, int c, int k, int l, int r){
		if (r <= b || c <= l)
			return Integer.MAX_VALUE;
		if((b<=l && r<=c))
			return a[k];
		
		int o1 = query(b,c,(k*2)+1,l,(l+r)/2);
		int o2 = query(b,c,(k*2)+2,(l+r)/2,r);
		return Integer.min(o1, o2);	
	}
	
	public int findSum(int b, int c){
		if(b==c)
			return a[b+n-2];
		return a[b+n-2]+ findSum(b+1,c);
	}
}