1 files changed, 56 insertions, 0 deletions
diff --git a/p102/p_102.go b/p102/p_102.go
new file mode 100644
index 0000000..d7e3f57
--- /dev/null
+++ b/p102/p_102.go
@@ -0,0 +1,56 @@
+package main
+
+import (
+  "fmt"
+  "bufio"
+  "os"
+  "log"
+)
+
+type Point struct {
+  x,y int
+}
+
+type Triangle struct {
+  a,b,c Point
+}
+
+func readTriangle( str string ) (ret Triangle) {
+  fmt.Sscanf(str, "%d,%d,%d,%d,%d,%d", &ret.a.x, &ret.a.y, &ret.b.x, &ret.b.y, &ret.c.x, &ret.c.y)
+  return ret
+}
+func det( a, b Point) int {
+  return a.x*b.y - a.y*b.x;
+}
+
+func signe( c, a Point) bool {
+  return det(Point{ c.x - a.x, c.y - a.y}, Point{ -a.x, -a.y }) < 0
+}
+
+
+func main() {
+  file, err := os.Open("p102_triangles.txt")
+  cmp := 0
+
+  if err != nil {
+    log.Fatal(err)
+  }
+  
+  defer file.Close()
+  
+  scan := bufio.NewScanner(file)
+  scan.Split(bufio.ScanLines)
+
+  for scan.Scan() {
+    trian := readTriangle(scan.Text())
+
+    sign := signe( trian.c, trian.a )
+
+    if signe( trian.a, trian.b) == sign && signe( trian.b, trian.c ) == sign {
+      cmp++
+    }
+  }
+
+  fmt.Print(cmp);
+}
+