[백준/Java] 11659 구간 합 구하기 4

import java.util.StringTokenizer;

import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;

class Main {
    public static void main(String[] args) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(br.readLine());

        int N = Integer.parseInt(st.nextToken());
        int M = Integer.parseInt(st.nextToken());

        int[] arr = new int[N];

        st = new StringTokenizer(br.readLine());

        for(int i=0;i<N;i++)
            arr[i] = Integer.parseInt(st.nextToken());

        for(int i=0;i<M;i++) {
            int sum = 0;
            st = new StringTokenizer(br.readLine());
            int start = Integer.parseInt(st.nextToken());
            int end = Integer.parseInt(st.nextToken());

            for(int j=start-1;j<end;j++)
                sum += arr[j];

            System.out.println(sum);       
        }
    }
}

import java.util.StringTokenizer;

import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;

class Main {
    public static void main(String[] args) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(br.readLine());

        int N = Integer.parseInt(st.nextToken());
        int M = Integer.parseInt(st.nextToken());

        int[] arr = new int[N+1];

        st = new StringTokenizer(br.readLine());

        arr[0] = 0;

        for(int i=0;i<N;i++)
            arr[i+1] = arr[i] + Integer.parseInt(st.nextToken());

        for(int i=0;i<M;i++) {
            st = new StringTokenizer(br.readLine());
            int start = Integer.parseInt(st.nextToken());
            int end = Integer.parseInt(st.nextToken());

            System.out.println(arr[end] - arr[start-1]);   
        }
    }
}