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#include <stdio.h>
#include <stdbool.h>
typedef struct
{
int a[2],b[2],c[2];
} triangle;
static inline void
vsub(int d[], int s[], int t[])
{
d[0] = s[0] - t[0];
d[1] = s[1] - t[1];
}
static int
ext_product(int s[], int t[])
{
return s[0] * t[1] - s[1] * t[0];
}
static int sign(int x)
{
if (x < 0)
return -1;
if (x > 0)
return 1;
return 0;
}
bool o_in_tri(triangle *t)
{
int ab[2], ac[2], bc[2];
vsub(ab, t->b, t->a);
vsub(ac, t->c, t->a);
vsub(bc, t->c, t->b);
/* sig(ABxAC) = sig(OBxOC) */
int sabc = sign(ext_product(ab, ac));
int sobc = sign(ext_product(t->b, t->c));
if (sabc != sobc)
return false;
/* sig(BAxBC) = sig(OAxOC) */
int sbac = sign(ext_product(bc, ab));
int soac = sign(ext_product(t->a, t->c));
if (sbac != soac)
return false;
/* sig(CAxCB) = sig(OAxOB) */
int scab = sign(ext_product(ac, bc));
int soab = sign(ext_product(t->a, t->b));
if (scab != soab)
return false;
return true;
}
int main()
{
triangle t;
int n = 0;
/* the data uses ',' to split the integers, process it with
* sed 's/,/ /g' first. */
while (scanf("%d%d%d%d%d%d", &t.a[0], &t.a[1], &t.b[0], &t.b[1],
&t.c[0], &t.c[1]) != EOF) {
if (o_in_tri(&t))
n++;
}
printf("%d\n", n);
}
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