ACM 507 Jill Rides Again

Maximum Subarray的題目，因為有 "If more than one segment is maximally nice, choose the one with the longest cycle ride (largest j-i). To break ties in longest maximal segments, choose the segment that begins with the earliest stop (lowest i)." 這個條件，所以必須開四個變數分別紀錄：
(1) Maximum Subarray的頭、尾
(2) 目前計算的Subarray的頭、尾


#include <stdio.h>

int main(void)
{
    int i, n, m, t, , p, q, val, sum, max, stop, start;
   
    scanf("%d", &n);
    for (t = 1; t <= n; t++)
    {
        scanf("%d", &m);
        max = sum = 0;
        p = q = start = stop = 1;
        for (i = 1; i < m; i++)
        {
            scanf("%d", &val);
            sum += val;
            if (sum >= 0)
            {
                q = i+1;
                if ((sum > max) || (sum == max && q-p > stop-start))
                {
                    max = sum;
                    start = p;
                    stop = q;
                }
            }
            else
            {
                sum = 0;
                p = q = i+1;
            }
        }
       
        if (max)
            printf("The nicest part of route %d is between stops %d and %d\n", t, start, stop);
        else
            printf("Route %d has no nice parts\n", t);
    }
   
    return 0;
}