POJ 3714 Raid

来源：互联网发布：vs code php开发环境编辑：程序博客网时间：2024/05/17 04:20
#include <stdio.h>#include <math.h>#define MAX 100001#define INF (1e+11)struct POINT{double x;double y;int isAgent;};int numOfStationsOrAgents;POINT pointArray[MAX * 2];int numOfPoints;int indexOfPoint;POINT leftMidPointArray[MAX];int numOfLeftMidPoints;int indexOfLeftMidPoint;POINT rightMidPointArray[MAX];int numOfRightMidPoints;int indexOfRightMidPoint;void pointCopy(POINT *to, POINT *from){to->x = from->x;to->y = from->y;to->isAgent = from->isAgent;}void sortPointsAccordingToX(int start, int end){if (start >= end){return;}while (start < end){int left = start;int right = end;POINT pivotPoint;pointCopy(&pivotPoint, &pointArray[start]);double pivotX = pivotPoint.x;while (left < right){while (left < right && pointArray[right].x >= pivotX){right--;}pointCopy(&pointArray[left], &pointArray[right]);while (left < right && pointArray[left].x <= pivotX){left++;}pointCopy(&pointArray[right], &pointArray[left]);}pointCopy(&pointArray[left], &pivotPoint);int pivot = left;sortPointsAccordingToX(start, pivot - 1);start = pivot + 1;}}double getDist(POINT from, POINT to){if (from.isAgent == to.isAgent){return INF;}double deltaX = from.x - to.x;double deltaY = from.y - to.y;return sqrt(deltaX * deltaX + deltaY * deltaY);}double getMinDist(int left, int right){double minDist = INF;if (left == right){return minDist;}if (left + 1 == right){return getDist(pointArray[left], pointArray[right]);}int mid = (left + right) >> 1;double leftMinDistSquare = getMinDist(left, mid);double rightMinDistSquare = getMinDist(mid + 1, right);minDist= (leftMinDistSquare < rightMinDistSquare ? leftMinDistSquare : rightMinDistSquare);numOfLeftMidPoints = 0;for (indexOfPoint = mid; indexOfPoint >= left; indexOfPoint--){double deltaX = pointArray[mid].x - pointArray[indexOfPoint].x;if ( deltaX < minDist){++numOfLeftMidPoints;pointCopy(&leftMidPointArray[numOfLeftMidPoints], &pointArray[indexOfPoint]);}}numOfRightMidPoints = 0;for (indexOfPoint = mid; indexOfPoint <= right; indexOfPoint++){double deltaX = pointArray[indexOfPoint].x - pointArray[mid].x;if ( deltaX < minDist){++numOfRightMidPoints;pointCopy(&rightMidPointArray[numOfRightMidPoints], &pointArray[indexOfPoint]);}}for (indexOfLeftMidPoint = 1; indexOfLeftMidPoint <= numOfLeftMidPoints; indexOfLeftMidPoint++){for (indexOfRightMidPoint = 1; indexOfRightMidPoint <= numOfRightMidPoints; indexOfRightMidPoint++){double dist = getDist( leftMidPointArray[indexOfLeftMidPoint], rightMidPointArray[indexOfRightMidPoint]);if (dist < minDist){minDist = dist;}}}return minDist;}int main(){//freopen("input.txt", "r", stdin);int numOfTestCases;scanf("%d", &numOfTestCases);while (numOfTestCases--){scanf("%d", &numOfStationsOrAgents);numOfPoints = numOfStationsOrAgents * 2;for (indexOfPoint = 1; indexOfPoint <= numOfStationsOrAgents; indexOfPoint++){scanf("%lf %lf", &pointArray[indexOfPoint].x, &pointArray[indexOfPoint].y);pointArray[indexOfPoint].isAgent = 0;}for (  ; indexOfPoint <= numOfPoints; indexOfPoint++){scanf("%lf %lf", &pointArray[indexOfPoint].x, &pointArray[indexOfPoint].y);pointArray[indexOfPoint].isAgent = 1;}sortPointsAccordingToX(1, numOfPoints);printf("%.3f\n", getMinDist(1, numOfPoints) );}return 0;}
0 0