17386

이수민/17386.c

@@ -0,0 +1,29 @@
+#include <stdio.h>
+#include <stdlib.h>
+typedef struct {
+    long long int x,y;
+}st;
+int ccw(st p1, st p2, st p3) {
+    long long int s = (p1.x*p2.y + p2.x*p3.y + p3.x*p1.y) - (p1.x*p3.y + p2.x*p1.y + p3.x*p2.y);
+    if(s > 0) return 1;
+    else if(s == 0) return 0;
+    return -1;
+}
+int isCross(st p1, st p2, st p3, st p4) {
+    int p1p2 = ccw(p1, p2, p3) * ccw(p1, p2, p4);
+    int p3p4 = ccw(p3, p4, p1) * ccw(p3, p4, p2);
+    return p1p2 <= 0 && p3p4 <= 0;
+}
+int main()
+{
+    int x1,x2,x3,x4,y1,y2,y3,y4;
+    scanf("%d %d %d %d",&x1,&y1,&x2,&y2);
+    scanf("%d %d %d %d",&x3,&y3,&x4,&y4);
+    st p1 = {x1, y1};
+    st p2 = {x2, y2};
+    st p3 = {x3, y3};
+    st p4 = {x4, y4};
+
+    printf("%d",isCross(p1, p2, p3, p4));
+    return 0;
+}