{"id":309,"date":"2013-01-20T13:08:00","date_gmt":"2013-01-20T05:08:00","guid":{"rendered":"http:\/\/nike0good.jp1.rpvhost.net\/214"},"modified":"2013-01-20T13:08:00","modified_gmt":"2013-01-20T05:08:00","slug":"poj_2007_the_volume_parcels_algorithm_gift_wrapping_algorithm__ostream","status":"publish","type":"post","link":"https:\/\/nike0good.com\/?p=309","title":{"rendered":"POJ 2007(\u5377\u5305\u88f9\u7b97\u6cd5(Gift Wrapping Algorithm)+ostream)"},"content":{"rendered":"

<\/span><\/p>\n\n\n\n
\n
Language:\n\n\n\n
Time Limit:<\/strong> 1000MS<\/td>\n <\/td>\nMemory Limit:<\/strong> 30000K<\/td>\n<\/tr>\n
Total Submissions:<\/strong> 5602<\/td>\n <\/td>\nAccepted:<\/strong> 2664<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Description<\/p>\n

\n \u51f8\u5305\u6c42\u6cd5\u5982\u56fe\uff1a
\n
\"\"
\n<\/center>
\n

\n<\/center>
\n
\"\"
\n<\/center>\n<\/div>\n

Input<\/p>\n

\n\u70b9\u6570\u4e0d\u8d85\u8fc7 50.\u6bcf\u884c\u8f93\u5165\u7684\u5750\u6807\u4e3a\u6574\u6570\u4e14\u8303\u56f4\u5728 -999..999. \u6570\u636e\u4ee5(0,0)\u5f00\u5934,\u4fdd\u8bc1\u6240\u6709\u70b9\u5fc5\u80fd\u6784\u6210\u51f8\u5305,\u9664\u7b2c1\u4e2a\u70b9\u5916\u6ca1\u6709\u70b9\u5728\u5750\u6807\u8f74\u4e0a\u6216\u7b2c\u4e8c\u8c61\u9650,\u6ca1\u7528\u4e09\u70b9\u5171\u7ebf.<\/div>\n

Output<\/p>\n

\n\u6bcf\u884c\u8f93\u51fa\u4e00\u4e2a\u5750\u6807(x,y)\uff0c\u4ee5(0,0)\u5f00\u5934,\u9006\u65f6\u9488\u8f93\u51fa.<\/div>\n

Sample Input<\/p>\n

0 0\n70 -50\n60 30\n-30 -50\n80 20\n50 -60\n90 -20\n-30 -40\n-10 -60\n90 10\n<\/pre>\n
Sample Output<\/p>\n
(0,0)\n(-30,-40)\n(-30,-50)\n(-10,-60)\n(50,-60)\n(70,-50)\n(90,-20)\n(90,10)\n(80,20)\n(60,30)\n<\/pre>\n
Source<\/p>\n
\nRocky Mountain 2004<\/a><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
<\/span>
\n\u6ce8\u610fistream\u548costream\u7684\u5199\u6cd5<\/p>\n
\u5b83\u5fc5\u987b\u662f\u53cb\u5143\u51fd\u6570\uff08\u5982\u679c\u662f\u6210\u5458\u51fd\u6570\uff0c\u5219\u5fc5\u987b\u4ee5const P\u4e3a\u5f00\u5934\uff0c\u8fd9\u663e\u7136\u4e0d\u884c\uff09<\/span><\/p>\n
\u5b83\u8fd4\u56de\u4e00\u4e2a\u6307\u5411ostream\u7684\u6307\u9488\uff0c\u524d\u9762\u53ef\u4ee5\u63a5ostream(cout<<a<<b;<\/strong>)<\/span>\uff0c\u8fd8\u6709\u4e00\u4e2a\u5143\u7d20\uff08\u8981\u8f93\u5165\u7684\uff09   <\/span><\/p>\n
 friend ostream& operator<<(ostream& cout,P &a)<\/span><\/p>\n
{
\n<\/span>cout<<"("<<a.x<<','<<a.y<<')'<<endl; 
\n\/\/\u628a\u8981\u8f93\u51fa\u7684\u5185\u5bb9\u63a8\u8fdb\u8f93\u51fa\u6d41<\/strong>
\n<\/span>return cout;
\n}
\n<\/span><\/p>\n
\u63a5\u4e0b\u6765\u8bb2\u5377\u5305\u88f9\u7b97\u6cd5\uff1a<\/span><\/p>\n
\u6211\u4eec\u5148\u627e\u5230\u4e00\u4e2a\u5728\u51f8\u5305\u4e0a\u7684\u70b9\uff0c\u7136\u540e\u5377\u8fc7\u53bb<\/span><\/p>\n
\"\"
\n<\/span><\/p>\n

\n<\/span><\/p>\n
\u4f2a\u4ee3\u7801\u5982\u4e0b\uff1a<\/span><\/p>\n
\u521d\u59cb\u5316st[]=0,j=0,endpoint=P0<\/span><\/p>\n
do<\/span><\/p>\n
{<\/span><\/p>\n
<\/span>\u5c06endpoint\u52a0\u5165\u961f\u5217st.<\/span><\/p>\n
<\/span>\u627e\u5230\u4efb\u610f\u4eceP0\u70b9\u51fa\u53d1\uff0c\u8f6c\u5411\u6700\u53f3\u7684\u70b9P<\/span><\/p>\n
<\/span>endpoint=P<\/span><\/p>\n
}until endpoint=P0<\/span><\/p>\n

\n<\/span><\/p>\n
<\/span><\/p>\n
#include<cstdio>\n#include<iostream>\n#include<cstdlib>\n#include<cstring>\n#include<algorithm>\n#include<functional>\nusing namespace std;\n#define MAXN (50+10)\nstruct P\n{\n    int x,y;\n    P(){}\n    P(int _x,int _y):x(_x),y(_y){}\n    friend ostream& operator<<(ostream& cout,P &a)\n\t{\n\t\tcout<<"("<<a.x<<','<<a.y<<')'<<endl;\n\t\treturn cout;\n\n\t}\n}a[MAXN];\nstruct V\n{\n    int x,y;\n    V(){}\n    V(int _x,int _y):x(_x),y(_y){}\n    V(P A,P B):x(B.x-A.x),y(B.y-A.y){}\n};\nint operator*(V a,V b)\n{\n    return a.x*b.y-a.y*b.x;\n}\nint n,st[MAXN];\nint main()\n{\n\/\/\tfreopen("poj2007.in","r",stdin);\n    int n=1;\n\twhile (scanf("%d%d",&a[n].x,&a[n].y)!=-1) n++; \/\/scanf\u8bfb\u5165\u5931\u8d25\u8fd4\u56de-1\n    n--;\n\n    int endpoint=1,j=1;\n\tdo\n\t{\n\t\tcout<<a[st[j++]=endpoint];\n\t\tint k=(endpoint+1)%n+1;\n\t\tfor (int i=1;i<=n;i++)\n\t\t\tif (endpoint!=i&&V(a[endpoint],a[i])*V(a[endpoint],a[k])>0) k=i;\n\t\tendpoint=k;\n\t\/\/\tcout<<endpoint<<' ';\n\t}while (endpoint!=1);\n\n\n    return 0;\n}<\/pre>\n<\/p>\n

\n<\/span><\/p>\n

\n<\/span><\/p>\n

\n<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"
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