add sol

leetcode/leetcode75/374.GuessNumberHigherOrLower/guessNumberHigherOrLower.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"fmt"
+)
+
+/**
+ * Forward declaration of guess API.
+ * @param  num   your guess
+ * @return 	     -1 if num is higher than the picked number
+ *			      1 if num is lower than the picked number
+ *               otherwise return 0
+ * func guess(num int) int;
+ */
+
+var pick = 6
+
+func guess(num int) int {
+	if num == pick {
+		return 0
+	} else if num > pick {
+		return -1
+	}
+	return 1
+}
+
+func guessNumber(n int) int {
+	left, right := 1, n
+	for left < right {
+		mid := left + (right-left)>>1
+		if guess(mid) <= 0 {
+			right = mid
+		} else {
+			left = mid + 1
+		}
+	}
+	return left
+}
+
+func main() {
+	n := 10
+	fmt.Println(guessNumber(n))
+}