hdu 1053 (huffman coding, greedy algorithm, std::partition, std::priority_queue )

huffman coding, greedy algorithm.
std::priority_queue, std::partition,
when i use the three commented lines, excution time increase to 15ms from 0ms, due to worse locality?
thanks to
http://acm.hdu.edu.cn/discuss/problem/post/reply.php?action=support&postid=5699&messageid=2&deep=1
for the provided test case. below is an excerpt,
input
AAAAABCD
THE_CAT_IN_THE_HAT
A
ABCD
AAAAA
ABCDEFGH
END

output
64 13 4.9
144 51 2.8
8 1 8.0
32 8 4.0
40 5 8.0
64 24 2.7

#include <cstdio>#include <queue>#include <algorithm>#include <functional>int main() {    //freopen("input.txt","r",stdin);    const int MAXSIZE=256;    char line[MAXSIZE], *q;    //int times[MAXSIZE]={0}, i,tmp,len, sum,res, *p,*pu=times+1,*pn=times+(2-'0'),*pc=times+(12-'A');    int times[MAXSIZE]={0}, i,tmp,len, sum,res, *p,*pu=times+1,*pn=times+2,*pc=times+12;    std::priority_queue<int, std::vector<int>, std::greater<int> > my_min_heap;    while(scanf("%256s",line)==1 && strcmp(line,"END")!=0) {        for(q=line;tmp=*q;++q) {            //if(tmp>='A' && tmp<='Z') ++pc[tmp];            //else if(tmp>='0' && tmp<='9') ++pn[tmp];            if(tmp>='A' && tmp<='Z') ++pc[tmp-'A'];            else if(tmp>='0' && tmp<='9') ++pn[tmp-'0'];            else ++*pu;        }        p=std::partition(pu,pu+37,[](int i) { return i>0; });        len=p-pu;        if(len<2) { res=strlen(line); }        else {            while(--p!=times) my_min_heap.push(*p);            for(res=0,i=1;i<len;++i) {                sum=my_min_heap.top(); my_min_heap.pop();                sum+=my_min_heap.top(); my_min_heap.pop();                my_min_heap.push(sum);                res+=sum;            }            my_min_heap.pop();        }        std::fill(pu,pu+len,0);        len=strlen(line)<<3;        printf("%d %d %.1f\n",len,res,(double)len/res);    }    return 0;}