【HDOJ】1007 Quoit Design
简单数学题，wa的不明所以，ac的也不明所以。
1 #include <stdio.h> 2 #include <stdlib.h> 3 #include <math.h> 4 5 #define MAXNUM 100005 6 #define MAXN 999999999 7 8 typedef struct { 9 double x, y; 10 } point_st; 11 12 point_st points[MAXNUM]; 13 14 int comp(const void *a, const void *b) { 15 if ( ((point_st *)a)->y == ((point_st *)b)->y ) 16 return ((point_st *)a)->x < ((point_st *)b)->x ? 1:-1; 17 else 18 return ((point_st *)a)->y < ((point_st *)b)->y ? 1:-1; 19 } 20 21 int comp1(const void *a, const void *b) { 22 if ( ((point_st *)a)->x == ((point_st *)b)->x ) 23 return ((point_st *)a)->y < ((point_st *)b)->y ? 1:-1; 24 else 25 return ((point_st *)a)->x < ((point_st *)b)->x ? 1:-1; 26 } 27 28 int main() { 29 int n; 30 int i; 31 double tmp, min; 32 33 while (scanf("%d", &n)!=EOF && n) { 34 for (i=0; i<n; ++i) 35 scanf("%lf%lf", &points[i].x, &points[i].y); 36 qsort(points, n, sizeof(point_st), comp); 37 min = MAXN; 38 for (i=1; i<n; ++i) { 39 tmp = pow(points[i].x-points[i-1].x, 2) + pow(points[i].y-points[i-1].y, 2); 40 tmp = sqrt(tmp) / 2.0f; 41 if (tmp < min) 42 min = tmp; 43 } 44 qsort(points, n, sizeof(point_st), comp1); 45 for (i=1; i<n; ++i) { 46 tmp = pow(points[i].x-points[i-1].x, 2) + pow(points[i].y-points[i-1].y, 2); 47 tmp = sqrt(tmp) / 2.0f; 48 if (tmp < min) 49 min = tmp; 50 } 51 printf("%.2lf\n", min); 52 } 53 54 return 0; 55 }
