Java 구간 합

public 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 suNo = Integer.parseInt(st.nextToken());
        int quizNo = Integer.parseInt(st.nextToken());

        long[] S = new long[suNo + 1];
        st = new StringTokenizer(br.readLine());

        for (int i =1; i <= suNo; i++ ) {
            S[i] = S[i -1] + Integer.parseInt(st.nextToken());
        }

        for (int q=0; q< quizNo; q++) {
            st = new StringTokenizer(br.readLine());
            int i = Integer.parseInt(st.nextToken());
            int j = Integer.parseInt(st.nextToken());
            System.out.println(S[j]-S[i-1]);
        }
    }
}