猜大小。py&cpp实现

374. Guess Number Higher or Lower/main.cpp

@@ -0,0 +1,25 @@
+// Forward declaration of guess API.
+// @param num, your guess
+// @return -1 if my number is lower, 1 if my number is higher, otherwise return
+// 0
+int guess(int num);
+
+class Solution {
+public:
+  int guessNumber(int n) {
+    int left = 1, right = n;
+    int res, mid;
+    while (left < right) {
+      mid = (right - left) / 2 + left;
+      res = guess(mid);
+      if (res == -1) {
+        right = mid - 1;
+      } else if (res == 1) {
+        left = mid + 1;
+      } else {
+        return mid;
+      }
+    }
+    return left;
+  }
+};

374. Guess Number Higher or Lower/main.py

@@ -0,0 +1,22 @@
+# The guess API is already defined for you.
+# @param num, your guess
+# @return -1 if my number is lower, 1 if my number is higher, otherwise return 0
+# def guess(num):
+
+class Solution(object):
+    def guessNumber(self, n):
+        """
+        :type n: int
+        :rtype: int
+        """
+        left, right = 1, n
+        while left < right:
+            mid = (left + right)//2
+            res = guess(mid)
+            if res == -1:
+                right = mid - 1
+            elif res == 1:
+                left = mid + 1
+            else:
+                return mid
+        return left