最近点对算法最近点对问题

TR[k]=SR[j]; }
{ ( SR[i].y < SR[j].y ) TR[k]=SR[i];
TR[k]=SR[j]; } } (i<=m) { for( l=0;l<=m-i;l) { TR[k+l]=SR[i+l]; // 将剩余SR[i..m]复制到TR } }
{ for( l=0;l<=n-j;l) { TR[k+l]=SR[j+l]; // 将剩余SR[j..n]复制到TR
bool Brute_Force(const Pos& pos ,Closest_Pair& closest_pair , from , to) { for( i=from ;i<=to ;i) { for( j=i+1;j<=to ;j) { double next = Account_Distance_2(pos.p_pair[i] ,pos.p_pair[j]) ;//sqrt( ) (closest_pair.distance > next ) { closest_pair.pair_a = pos.p_pair[i] ; closest_pair.pair_b = pos.p_pair[j] ; closest_pair.distance = next ; } } }
最近点对算法:最近点对问题
疯狂代码 / ĵ:http://VC/Article66512.html
通过代码来学习例子看下面代码: //点结构 typedef struct Pair { x; y; } Pair ; //最近点对结构 typedef struct Closest_Pair { Pair pair_a ,pair_b ; double distance ; } Closest_Pair ; //点对结构 typedef struct Pos { Pair* p_pair ;
double distance ; } Closest_Pair ; typedef struct Pos { Pair* p_pair ; pair_nums ;//点对数目 } Pos ; //-------------------------------------------------------------TR1,s,m,t) ; // 将TR2[s..m]和TR2[m+1..t]归并到TR1[s..t]
delete TR2 ; }
// cout << " Hello " ;
} //---------------------------------------------------------------------------
void Comp_CP(const Pos& pos ,Closest_Pair& closest_pair , mid , mid_value) { i,j; distance = sqrt( closest_pair.distance ) ; i = mid ; while( i >= 0 && pos.p_pair[i].x > (mid_value-distance) ) { j = mid ;
}
} } //--------------------------------------------------------------------------void MSort(char sign ,Pair SR ,Pair TR1 ,long s , long t) { // 将SR[s..t]归并排序为TR1[s..t].
( (A.x-B.x)*(A.x-B.x)+(A.y-B.y)*(A.y-B.y) ) ; }
//--------------------------------------------------------------------------void Pr_Pos(ostream& outs ,const Pos& pos ,const Closest_Pair& closest_pair ) { outs << "\n\n\n 随机产生点对如下:\n" ; for( i=0 ;i<pos.pair_nums ;i) { outs << " (" << pos.p_pair[i].x << " , " << pos.p_pair[i].y << " ) " ; ((i+1)%50) { outs << endl ; } } outs << "\n\n 由以上点对可得最近点对为: ( " << closest_pair.pair_a.x << " , " << closest_pair.pair_a.y << " ) ,( " << closest_pair.pair_b.x << " , " << closest_pair.pair_b.y << " ) " ; outs << "\n 该点对距离为:" << closest_pair.distance << endl ; } //---------------------------------------------------------------------------
while( pos.p_pair[j].x < (mid_value+distance) && j < pos.pair_nums ) { ( pos.p_pair[j].y > (pos.p_pair[i].y+distance) || pos.p_pair[j].y < (pos.p_pair[i].y-distance) ) //判断在y轴是否出界 continue ; double next = Account_Distance_2( pos.p_pair[i] ,pos.p_pair[j]);//sqrt( ) (closest_pair.distance > next ) { closest_pair.pair_a = pos.p_pair[i] ; closest_pair.pair_b = pos.p_pair[j] ; closest_pair.distance = next ; cout << "Comp_CP: " << closest_pair.distance << endl ; }
{ mid = (from+to)/2 ; mid_value = pos.p_pair[mid].x ;
Divide_and_Conquer(pos ,closest_pair ,from ,mid) ;
Divide_and_Conquer(pos ,closest_pair ,mid+1 ,to) ; Comp_CP(pos ,closest_pair ,mid ,mid_value) ; }
pair_nums ;//点对数目 } Pos
//蛮力法:分别计算每对点的间距离然后找距离最小那对 bool Brute_Force(const Pos& pos ,Closest_Pair& closest_pair , from , to) { for( i=from ;i<=to ;i) { for( j=i+1;j<=to ;j) { double next= Account_Distance_2(pos.p_pair[i] ,pos.p_pair[j]) ; (closest_pair.distance > next ) { closest_pair.pair_a = pos.p_pair[i] ; closest_pair.pair_b = pos.p_pair[j] ; closest_pair.distance = next ; } } }
true ; }
//-------------------------------------------------------------------------// 对顺序表L作归并排序 void Merge(char sign ,Pair SR ,Pair TR ,long i ,long m ,long n) { // 将有序SR[i..m]和SR[m+1..n]归并为有序TR[i..n] // j,k,l; for( j=m+1,k=i;i<=m&&j<=n;k) // 将SR中记录由小到大地并入TR { (sign'x') { ( SR[i].x < SR[j].x ) TR[k]=SR[i];
(st) { TR1[s] = SR[s]; }
{ // m ; length = t-s+1 ;// Pair* TR2 = Pair[pos.pair_nums]; long m = (s+t)/2; // 将SR[s..t]平分为SR[s..m]和SR[m+1..t] MSort(sign ,SR,TR2,s,m) ; // 递归地将SR[s..m]归并为有序TR2[s..m] MSort(sign ,SR,TR2,m+1,t) ; // 递归地将SR[m+1..t]归并为有序TR2[m+1..t]
; }
# "Head.h" //--------------------------------------------------------------------------typedef RedType ; typedef struct Pair { x; y; } Pair ; typedef struct Closest_Pair { Pair pair_a ,pair_b ;