第十四届蓝桥杯集训——练习解题阶段(无序阶段)-ALGO-459 区间求和

#include<stdio.h>
#include<math.h>
int main() {
	int n;
	scanf("%d",&n);
	int a[2000],i;
	for (i = 0; i < n; i++) {
		scanf("%d",&a[i]);
	}
	int q,x,y,sum=0;
	scanf("%d", &q);
	while (q!=0)
	{
		scanf("%d", &x);
		scanf("%d", &y);
		for (i = x - 1; i <= y - 1; i++) {
			sum += a[i];
		}
		printf("%d\n", sum);
		sum = 0; q--;
	}

	return 0;
}

#include<stdio.h>
int main() {
	int n,q,i,j,k,sum=0;
	int a[2001];
	int x[2001],y[2001];
	scanf("%d",&n);
	for(i=1; i<=n; i++) {
		scanf("%d",&a[i]);
	}
	scanf("%d",&q);
	for(j=0; j<q; j++) {
		scanf("%d %d",&x[j],&y[j]);
	}
	if(n<=2000&&q<=2000) {
		for(j=0; j<q; j++) {
			for(k=x[j]; k<=y[j]; k++)
				sum += a[k];
			printf("%d\n",sum);
			sum = 0;
		}
	} else
		printf("输入有误\n");
	return 0;
}

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class Main {

	public static void main(String[] args) throws IOException {
		// TODO Auto-generated method stub
		Reader sc=new Reader();
		PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));
		int n = sc.nextInt();
		long arr[]	= new long[n];
		for (int i = 0; i < n; i++) {
			arr[i] = sc.nextInt();
		}
		int q = sc.nextInt();
		long[] re = new long[q];
		int index = 0;
		for (int i = 0; i < q; i++) {
			long sum = 0;
			int a = sc.nextInt();
			int b = sc.nextInt();
			for (int j = a-1; j <= b-1; j++) {
				sum = arr[j] + sum;
			}
			re[index++] = (int) sum;
			
		}
		for (int i = 0; i < re.length; i++) {
			System.out.println(re[i]);
		}

	}
	static class Reader {
	    static BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
	    static StringTokenizer tokenizer = new StringTokenizer("");
	    /** 获取下一段文本 */
	    static String next() throws IOException {
	        while ( ! tokenizer.hasMoreTokens() ) {
	            tokenizer = new StringTokenizer(reader.readLine());
	        }
	        return tokenizer.nextToken();
	    }
	    static int nextInt() throws IOException {
	        return Integer.parseInt( next() );
	    }
	    static double nextDouble() throws IOException {
	        return Double.parseDouble( next() );
	    }
	}

}

import os
import sys

def main():
    n = int(input())
    array = [int(i) for i in input().split()]
    for i in range(1,n):
        array[i] += array[i-1]
    array.insert(0,0)

    q = int(input())
    for _ in range(q):
        str = input().split()
        start = int(str[0])
        end = int(str[1])
        print(array[end] - array[start-1])


if __name__ == "__main__":
    main()