//?distance.cpp?:?Defines?the?entry?point?for?the?console?application.
//

#include?“stdafx.h“
#include?
#include?

typedef?struct?tagPoint
{
	double?x;
	double?y;
}POINT;

typedef?struct?tagLine
{
	POINT?p1;
	POINT?p2;
}LINE;

double?distance（?POINT&?pt?LINE&?line）
{
	double?x1?y1?x2?y2?x3?y3;????
????double?px?=?line.p2.x?-?line.p1.x;
????double?py?=?line.p2.y?-?line.p1.y;
????double?som?=?px?*?px?+?py?*?py;
????double?u?=??（（pt.x?-?line.p1.x）?*?px?+?（pt.y?-?line.p1.y）?*?py）?/?som;
????if?（u?>?1）?{
????????u?=?1;
????}
????if?（u?????????u?=?0;
????}
????//the?closest?point
????double?x?=?line.p1.x?+?u?*?px;
????double?y?=?line.p1.y?+?u?*?py;
????double?dx?=?x?-?pt.x;
????double?dy?=?y?-?pt.y;??????
????double?dist?=?sqrt（dx*dx?+?dy*dy）;
	
	return?dist;
}


int?main（int?argc?char*?argv[]）
{
	POINT?pt;
	pt.x?=?0;
	pt.y?=?0;

	LINE?line;
	line.p1.x?=?100;
	line.p1.y?=?-100;

	line.p2.x?=?100;
	line.p

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????1087??2013-04-09?17:22??distance.cpp

?????文件???????4560??2013-04-09?17:11??distance.dsp

?????文件????????539??2013-04-09?17:11??distance.dsw

?????文件??????33792??2013-04-09?17:22??distance.ncb

?????文件??????48640??2013-04-09?17:22??distance.opt

?????文件????????250??2013-04-09?17:22??distance.plg

?????文件???????1220??2013-04-09?17:11??ReadMe.txt

?????文件????????295??2013-04-09?17:11??StdAfx.cpp

?????文件????????769??2013-04-09?17:11??StdAfx.h

?????文件?????229428??2013-04-09?17:21??Debug\distance.exe

?????文件?????258196??2013-04-09?17:21??Debug\distance.ilk

?????文件???????6298??2013-04-09?17:21??Debug\distance.obj

?????文件?????213872??2013-04-09?17:11??Debug\distance.pch

?????文件?????525312??2013-04-09?17:21??Debug\distance.pdb

?????文件???????1884??2013-04-09?17:11??Debug\StdAfx.obj

?????文件??????50176??2013-04-09?17:22??Debug\vc60.idb

?????文件??????69632??2013-04-09?17:21??Debug\vc60.pdb

?????目錄??????????0??2013-04-09?17:21??Debug

-----------?---------??----------?-----??----

??????????????1445950????????????????????18