#include?
#include?
#include?
#include?
#include?
#include?
#include?
using?namespace?std;
pthread_mutex_t?mutex?=?PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t?cond?=?PTHREAD_COND_INITIALIZER;
struct?thr?{
????long?long?tstarttend;
};
long?long?NN2;
double?ans?=?0.0;
int?timesover;
thr?a[10001];
void?*thread（void*a）{
????double?t;
????thr?m?=?*（thr*）a;
????for（long?long?i?=?m.tstart;?i?????????t?+=?1.0/（N2+（i+0.5）*（i+0.5））;
????}
????pthread_mutex_lock（&mutex）;
????ans?+=?t;
????over++;
????pthread_mutex_unlock（&mutex）;
????void*?statu;
????pthread_exit（&statu）;
};
int?main（int?argc?char*?argv[]）{
????struct?timeval?tv;
????gettimeofday（&tvNULL）;
????double?t_start?t_end;
????long?long?st?=?0;
????t_start?=?（double）tv.tv_sec?+?（double）tv.tv_usec/1000000.0;
????int?i;
????long?long?len;
????pthread_t?pthr[10001];
????//thr?a[10001];
????times?=?atoi（argv[1]）;??//線程數
????N?=?atoi（argv[2]）;??????//總數
????len?=?（N+times-1）/times;
????N2?=?N*N;

????for（i?=?0;?i?????????a[i].tstart?=?st;
????????a[i].tend?=?min（st+lenN）;
????????st?=?st?+?len;
????????pthread_create（&pthr[i]NULLthread&a[i]）;
????}
????while（over!=times）{
????????usleep（3）;
????}
????ans?=?4.0*N*ans;
????pthread_mutex_destroy（&mutex）;
????gettimeofday（&tvNULL）;
????t_end?=?（double）tv.tv_sec?+?（double）tv.tv_usec/1000000.0;
????printf（“pthread_num:?%2d?N:?%9lld??pi:?%.12lf?time_cost:?%lf\n“timesNanst_end-t_start）;
????return?0;
}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2017-04-05?13:38??實驗一\
?????文件???????34837??2017-03-23?09:57??實驗一\hw1
?????文件????????1595??2017-03-23?09:57??實驗一\hw1.cpp
?????文件???????14400??2017-03-23?09:57??實驗一\hw1.o43227
?????文件?????????148??2017-03-18?19:41??實驗一\serial.cpp
?????文件????????3452??2017-03-23?09:57??實驗一\t1.pbs
?????目錄???????????0??2017-03-23?15:20??實驗二\
?????文件????72536322??2017-03-22?10:38??實驗二\Parallel_compumatrix.txt
?????文件????21143898??2017-03-22?13:33??實驗二\ans4pthread.txt
?????文件????21143898??2017-03-22?13:34??實驗二\ans9pthread.txt
?????文件????21143898??2017-03-22?13:33??實驗二\ans_serial.txt
?????文件???????33102??2017-03-23?09:57??實驗二\hw2
?????文件????????2658??2017-03-23?09:57??實驗二\hw2.cpp
?????文件????????4980??2017-03-23?09:57??實驗二\hw2.o43408
?????文件???????34041??2017-03-23?09:57??實驗二\hw2serial
?????文件????????1484??2017-03-23?09:57??實驗二\hw2serial.cpp
?????文件?????????680??2017-03-22?10:38??實驗二\matrix.cpp
?????文件???????61656??2017-03-22?10:38??實驗二\matrix.exe
?????文件????????2045??2017-03-22?10:38??實驗二\matrix.o
?????文件????????1402??2017-03-23?09:57??實驗二\t2.pbs
?????文件??????849926??2017-04-20?20:54??實驗報告一.pdf
?????文件??????729367??2017-04-20?20:54??實驗報告二.pdf