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#include<stdio.h>
typedef struct
{
int x,y;
int flag;
}point;
void ConvexHull(point p[],int n)
{
int i,j,k,a,b,c,sign1,sign2;
for(i = 0 ; i < n ; ++i)
for(j = i + 1 ; j < n ; ++j)
{
a = p[j].y - p[i].y;
b = p[j].x - p[i].x;
c = (p[i].x * p[j].y) - (p[j].x * p[i].y);
sign1 = 0;
sign2 = 0;
for(k = 0 ; k < n ; ++k)
{
if(k == i || k == j)
continue;
if(a * p[k].x + b * p[k].y == c) /*共线的情况,算两边都有该点*/
{
++sign1;
++sign2;
}
if(a * p[k].x + b * p[k].y > c)
++sign1;
if(a * p[k].x + b * p[k].y < c)
++sign2;
}
if((sign1 == n - 2) || (sign2 == n - 2))
{
p[i].flag = 1;
p[j].flag = 1;
}
}
}
int main()
{
int n,i;
scanf("%d",&n);
point p[n];
for(i = 0 ; i < n ; ++i)
scanf("%d %d",&p[i].x,&p[i].y);
for(i = 0 ; i < n ; ++i)
p[i].flag = 0;
ConvexHull(p,n);
printf("\nresult:\n");
for(i = 0 ; i < n ; ++i)
{
if(p[i].flag == 1)
printf("%d %d\n",p[i].x,p[i].y);
}
return 0;
}