1046. Shortest Distance (20)

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 … DN, where Di is the distance between the i-th and the (i+1)-st exits, and DN 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 9
3
1 3
2 5
4 1

Sample Output:

3
10
7

#include<iostream>using namespace std;int main(){    int m,n,all=0,temp;    cin>>n;    int *a=new int[n+1];    a[0]=0;    for(int i=1;i<=n;i++){        cin>>temp;        a[i]=temp+a[i-1];        all+=temp;    }    cin>>m;    while(m--){        int t1,t2,l=0;        cin>>t1>>t2;        if(t1>=t2)            l=a[t1-1]-a[t2-1];        else l=a[t2-1]-a[t1-1];        if(all-l<l)            l=all-l;        cout<<l<<endl;    }    return 0;}