UVA11136 Hoax or what STL 或者 HEAP

这道题题意不解释，《算法竞赛入门经典训练指南》里都有翻译，不知道的去看看吧。
本来博主写的堆：

/*************************************************************************    > File Name: \LJF\UVa\UVa_11136.cpp    > Author: ljf_cnyali    > Mail: [e-mail]    > Last modifiedz: 2016-08-27 14:59    > Description: This is a large group of God's program information. ************************************************************************/#include<iostream>#include<cstdio>#include<cstdlib>#include<cmath>#include<cstring>#include<ctime>#include<algorithm>#include<queue>#include<map>#include<set>#include<ctime>using namespace std;#define REP(i, a, b) for(long long i = (a), _end_ = (b);i <= _end_; ++i)const long long maxn = 10010000;long long max_heap[maxn], min_heap[maxn];long long max_len, min_len;void min_insert(long long x) {      min_heap[++min_len] = x;      long long k = min_len, t;      while(k > 1 && min_heap[k] < min_heap[k / 2]) {          t = min_heap[k];          min_heap[k] = min_heap[k / 2];          min_heap[k / 2] = t;          k /= 2;      }  }  void max_insert(long long x) {    max_heap[++max_len] = x;    long long k = max_len, t;    while(k > 1 && max_heap[k] > max_heap[k / 2]) {        t = max_heap[k];        max_heap[k] = max_heap[k / 2];        max_heap[k / 2] = t;        k /= 2;    }}int main() {      long long n, t, m, f, k;      while(1) {        scanf("%lld", &f);        memset(max_heap, 0, sizeof(max_heap));        memset(min_heap, 0, sizeof(min_heap));        max_len = 0;        min_len = 0;        if(f == 0)            return 0;        long long ans = 0;        REP(l, 1, f) {            scanf("%lld", &n);            REP(i, 1, n){                  scanf("%lld", &k);                  max_insert(k);                  min_insert(k);            }                ans += max_heap[1] - min_heap[1];            min_heap[1] = min_heap[min_len--];              k = 1;              while((2 * k <= min_len && min_heap[k] > min_heap[2 * k]) || (2 * k <= min_len && min_heap[k] > min_heap[2 * k + 1])) {                  m = 2 * k;                  if(m + 1 <= min_len && min_heap[m] > min_heap[m + 1])                      m++;                  t = min_heap[k];                  min_heap[k] = min_heap[m];                  min_heap[m] = t;                  k = m;              }            max_heap[1] = max_heap[max_len--];              k = 1;              while((2 * k <= max_len && max_heap[k] < max_heap[2 * k]) || (2 * k + 1 <= max_len && max_heap[k] < max_heap[2 * k + 1])) {                  m = 2 * k;                  if(m + 1 <= max_len && max_heap[m] < max_heap[m + 1])                      m++;                  t = max_heap[k];                  max_heap[k] = max_heap[m];                  max_heap[m] = t;                  k = m;              }          }        printf("%lld\n", ans);    }    return 0;  }  

WA了好久，都是Wrong answer，自己都觉得烦了。本来想写堆练下手，最后还是被迫选择了STL。
STL的代码在此：

/*************************************************************************    > File Name: \LJF\UVa\UVa_11136.cpp    > Author: ljf_cnyali    > Mail: [e-mail]    > Last modifiedz: 2016-08-27 14:59    > Description: This is a large group of God's program information. ************************************************************************/#include<iostream>#include<cstdio>#include<cstdlib>#include<cmath>#include<cstring>#include<ctime>#include<algorithm>#include<queue>#include<map>#include<set>#include<ctime>using namespace std;#define REP(i, a, b) for(long long i = (a), _end_ = (b);i <= _end_; ++i)multiset<long long> q;int main() {      long long n, t, m, f, k;      while(1) {        q.clear();              scanf("%lld", &f);        if(f == 0)            return 0;        long long ans = 0;        REP(l, 1, f) {            scanf("%lld", &n);            REP(i, 1, n){                  scanf("%lld", &k);                  q.insert(k);            }                auto s = q.begin(), e = q.end(); --e;            ans += *e - *s;            q.erase(e);             q.erase(q.begin());        }        printf("%lld\n", ans);    }    return 0;  }