1046. Shortest Distance

The task is really simple: given N exits on a highway which forms a simple cycle, you are supposed to tell the shortest distance between any pair of exits.

Input Specification:

Each input file contains one test case. For each case, the first line contains an integer N (in [3, 10⁵]), followed by N integer distances D₁ D₂ ... D_N, where D_i is the distance between the i-th and the (i+1)-st exits, and D_N is between the N-th and the 1st exits. All the numbers in a line are separated by a space. The second line gives a positive integer M (<=10⁴), with M lines follow, each contains a pair of exit numbers, provided that the exits are numbered from 1 to N. It is guaranteed that the total round trip distance is no more than 10⁷.

Output Specification:

For each test case, print your results in M lines, each contains the shortest distance between the corresponding given pair of exits.

Sample Input:

5 1 2 4 14 931 32 54 1

Sample Output:

3
10

7

#include <cstdio>

#include <cstdlib>

#include<iostream>

#include <deque>

#include <queue>

#include <cstring>

#include <vector>

#include<string>

#include <iomanip>

#include<algorithm>

using namespace std;

#define max1 10001

#define inf 6000

int main()

{

    int n,i,b,sum=0;

    cin>>n;

    vector<int>a(n+1);

    for(i=1;i<=n;i++)

    {

        cin>>b;

        sum+=b;

        a[i]=sum;

    }

    int m,right,left;

    cin>>m;

    for(i=0;i<m;i++)

    {

        cin>>left>>right;

        if(left>right)

            swap(left,right);

        int temp=a[right-1]-a[left-1];

        cout<<min(temp,sum-temp)<<endl;

    }

    return 0;

}