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 <stdio.h>
int main() {
int a1ToOtherDis[100] = {0}, N, sum = 0, len[100], questionNum, left, right, shun, ni;
scanf("%d", &N);
for (int i = 1; i <= N; i++) {
scanf("%d", &len[i]);
sum = sum + len[i];
a1ToOtherDis[i] = sum;
}
scanf("%d", &questionNum);
for (int i = 0; i < questionNum; i++) {
scanf("%d%d", &left, &right);
//保证 left<right
if (left > right) {
int temp = left;
left = right;
right = temp;
}
//顺时针
shun = a1ToOtherDis[right - 1] - a1ToOtherDis[left - 1];
ni = sum - shun;
if (shun < ni)
printf("%d\n", shun);
else
printf("%d\n", ni);
}
}
/*
5 1 2 4 14 9
3
1 3
2 5
4 1
*/
测试结果：
