Poj 2318 toys/poj 2398 (binary, cross set)

Calculate the number of toys in each grid. 2318 when the separator board is given, it is left-to-right, And the 2398 separator board is not sorted. You have to arrange it yourself. The output of the two questions is a little different. Nothing else ···

Poj 2318:

#include <iostream>using namespace std;#define MAX 5999struct CardBoard{int x1, y1, x2, y2;double k;  } board[MAX];int cell[MAX];int judge ( int x, int y, CardBoard & b ){double t = b.x1 - b.k * ( b.y1 - y );if ( x < t )return -1;else return 1;}int main(){int n, m;int x1, y1, x2, y2;int U, L, x, y, p, i;while ( scanf("%d",&n) ){if ( n == 0 ) break;scanf("%d%d%d%d%d",&m,&x1,&y1,&x2,&y2);for ( i = 1; i <= n; i++ ){scanf("%d%d",&U,&L);board[i].x1 = U;board[i].y1 = y1;board[i].x2 = L;board[i].y2 = y2;board[i].k = 1.0*(board[i].x1-board[i].x2)/(board[i].y1-board[i].y2);}board[0].x1 = x1;board[0].y1 = y1;board[0].x2 = x1;board[0].y1 = y2;board[n+1].x1 = x2;board[n+1].y1 = y1;board[n+1].x2 = x2;board[n+1].y2 = y2;memset(cell,0,sizeof(cell));while ( m-- ){scanf("%d%d",&x,&y);int mid, low = 0, high = n+1;while ( high - low > 1 ){mid = ( high + low ) / 2;p = judge(x,y,board[mid]);if ( p < 0 )high = mid;elselow = mid;}cell[low]++;}for ( i = 0; i <= n; i++ )printf("%d: %d\n", i, cell[i]);putchar('\n');}return 0;}

Poj 2398:

#include <iostream>using namespace std;#define MAX 2000struct CardBoard{int x1, y1, x2, y2;} board[MAX];int cell[MAX], mark[MAX];struct Item { int t, num; } cnt[MAX];int cmp1 ( const void * a, const void * b ){return ((CardBoard*)a)->x1 - ((CardBoard*)b)->x1;}int cmp2 ( const void * a, const void * b ){return ((Item*)a)->num - ((Item*)b)->num;}int judge ( int x, int y, CardBoard & b ){return  -((b.x1-b.x2)*(y-b.y2)-(b.y1-b.y2)*(x-b.x2));}int main(){int n, m;int x1, y1, x2, y2;int U, L, x, y, i;while ( scanf("%d",&n) ){if ( n == 0 ) break;scanf("%d%d%d%d%d",&m,&x1,&y1,&x2,&y2);for ( i = 1; i <= n; i++ ){scanf("%d%d",&U,&L);board[i].x1 = U;board[i].y1 = y1;board[i].x2 = L;board[i].y2 = y2;}board[0].x1 = x1;board[0].y1 = y1;board[0].x2 = x1;board[0].y1 = y2;board[n+1].x1 = x2;board[n+1].y1 = y1;board[n+1].x2 = x2;board[n+1].y2 = y2;qsort ( board, n+1, sizeof(CardBoard), cmp1);memset(cell,0,sizeof(cell));memset(mark,0,sizeof(mark));memset(cnt,0,sizeof(cnt));while ( m-- ){scanf("%d%d",&x,&y);int mid, low = 0, high = n+1;while ( high - low > 1 ){mid = ( high + low ) / 2;if ( judge ( x, y, board[mid] ) < 0 )high = mid;elselow = mid;}cell[low]++;}for ( i = 0; i <= n; i++ )if ( cell[i] ) mark[cell[i]]++;int k = 0;for ( i = 1; i <= n; i++ ){if ( mark[i] != 0 ){k++;cnt[k].t = mark[i];cnt[k].num = i;}}printf("Box\n");qsort(cnt+1,k,sizeof(Item),cmp2);for ( i = 1; i <= k; i++ )printf("%d: %d\n",cnt[i].num, cnt[i].t); }return 0;}