PAT 1046 Shortest Distance

#include <cstdio>
#include <cmath>
#include <vector>

using namespace std;

void swap(int& a, int& b) {
  int t = a;
  a = b;
  b = t;
}

int main() {
  int count;
  scanf("%d", &count);

  int totalDistance = 0;
  vector<int> distances(count + 1);
  distances[0] = 0;
  for (int i = 1; i <= count; i++) {
    int temp;
    scanf("%d", &temp);
    totalDistance += temp;
    distances[i] = totalDistance;
  }

  int rows, start, end;
  scanf("%d", &rows);
  while (rows--) {
    scanf("%d %d", &start, &end);
    if (start > end) swap(start, end);
    int thisDist = distances[end - 1] - distances[start - 1];
    int reverse = totalDistance - thisDist;
    printf("%d\n", reverse < thisDist ? reverse : thisDist);
  }

  return 0;
}