UVA 299 Train Swapping

题目

列车交换

分析

冒泡排序呀，问你要交换几次。

代码

#include <stdio.h>

int s;
int bubble(int* tr, int lo, int hi)
{
    int sorted = 1, tmp;
    while (++lo < hi)
        if (tr[lo - 1] > tr[lo]) {
            sorted = 0;
            tmp = tr[lo];
            tr[lo] = tr[lo - 1];
            tr[lo - 1] = tmp;
            s++;
        }
    if (!sorted) {
        bubble(tr, 0, hi--);
    } else {
        return s;
    }
}

int main(void) {
    int t, l, i, tr[55];
    scanf("%d", &t);
    while (t--) {
        scanf("%d", &l);
        for (i = 0; i < l; i++)
            scanf("%d", &tr[i]);
        s = 0;
        bubble(tr, 0, l);
        printf("Optimal train swapping takes %d swaps.\n", s);
    }
    return 0;
}