第一次在ubuntu下写程序,鼓捣了N久终于可以写东西了.从安装操作系统,编译软件,编译环境...
感觉自己弱成渣渣了...
一道水题 调了N久...
各种悲催..
#include<cstdio> #include<cstdlib> #include<algorithm> #include<cstring> #include<cmath> using namespace std; struct Point2D{ double x,y; }mesh[33][33],p[4][33]; struct Vector2D{ double x,y; }; Vector2D operator-(Point2D a,Point2D b) { Vector2D v; v.x=b.x-a.x;v.y=b.y-a.y; return v; } double operator^(Vector2D a,Vector2D b){ return fabs(a.x*b.y-b.x*a.y); } Point2D getPoint( Point2D a,Point2D b,Point2D c,Point2D d ) { Point2D temp; temp.x=((a.x*((c-b)^(d-b)))+(b.x*((c-a)^(d-a))))/(((c-b)^(d-b))+((c-a)^(d-a))); temp.y=((a.y*((c-b)^(d-b)))+(b.y*((c-a)^(d-a))))/(((c-b)^(d-b))+((c-a)^(d-a))); return temp; } double Area( Point2D a,Point2D b,Point2D c,Point2D d ){ return (fabs((c-a)^(d-a))+fabs((c-b)^(d-b))+fabs((a-c)^(b-c))+fabs((a-d)^(b-d)))/4; } int main() { //freopen( "input.txt","r",stdin ); //freopen( "output.txt","w",stdout ); int N; while( scanf("%d",&N)!=EOF ) { if( N==0 ) break; memset(p,0,sizeof(p)); p[0][0].x=0; p[0][0].y=0; p[0][N+1].x=1; p[0][N+1].y=0; p[1][0].x=0; p[1][0].y=1; p[1][N+1].x=1; p[1][N+1].y=1; for( int i=0;i<2;i++ ) for( int j=1;j<=N;j++ ) scanf( "%lf",&p[i][j].x ),p[i][j].y=i%2; for( int i=2;i<4;i++ ) for( int j=1;j<=N;j++ ) scanf( "%lf",&p[i][j].y ),p[i][j].x=i%2; for( int i=0;i<=N+1;i++ ) { for( int j=0;j<=N+1;j++ ) { //printf( "i=%d j=%d ",i,j ); if( i==0 ) { mesh[i][j]=p[0][j];continue; } if( i==N+1 ) { mesh[i][j]=p[1][j];continue; } if( j==0 ) { mesh[i][j]=p[2][i];continue; } if( j==N+1 ) { mesh[i][j]=p[3][i];continue; } //mesh[i][j].x=0.1;mesh[i][j].y=0.1;printf( "(%lf,%lf) ",mesh[i][j].x,mesh[i][j].y ); mesh[i][j]=getPoint( p[0][j],p[1][j],p[2][i],p[3][i] ); //printf( "(%lf,%lf) ",mesh[i][j].x,mesh[i][j].y ); } //printf( "\n" ); } /* for( int i=0;i<=N+1;i++ ){ for( int j=0;j<=N+1;j++ ) printf( "(%lf,%lf) ",mesh[i][j].x,mesh[i][j].y ); printf( "\n" ); } */ double ans=0; for( int i=0;i<=N;i++ ) for( int j=0;j<=N;j++ ) ans=max( ans,Area(mesh[i][j],mesh[i+1][j+1],mesh[i][j+1],mesh[i+1][j]) ); printf( "%.6f\n",ans ); } return 0; }