3 problems

Author: hitzzc

README.md

@@ -256,6 +256,9 @@ Golang solution for leetcode. For each problem, there is a simple *_test.go to t
 #### [368. Largest Divisible Subset](https://github.com/hitzzc/go-leetcode/tree/master/largest_divisible_subset)
 #### [371. Sum of Two Integers](https://github.com/hitzzc/go-leetcode/tree/master/sum_of_two_integers)
 #### [373. Find K Pairs with Smallest Sums](https://github.com/hitzzc/go-leetcode/tree/master/find_k_pairs_with_smallest_sums)
+#### [374. Guess Number Higher or Lower](https://github.com/hitzzc/go-leetcode/tree/master/guess_number_higher_or_lower)
+#### [375. Guess Number Higher or Lower II](https://github.com/hitzzc/go-leetcode/tree/master/guess_number_higher_or_lower_II)
+#### [376. Wiggle Subsequence](https://github.com/hitzzc/go-leetcode/tree/master/wiggle_subsequence)
 
 
 

guess_number_higher_or_lower/guess_number_higher_or_lower.cpp

@@ -0,0 +1,20 @@
+// 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 mid;
+        while (left <= right) {
+        	mid = left + (right-left)/2;
+        	cout << mid << endl;
+        	if (guess(mid) == 0) break;
+        	else if (guess(mid) > 0) left = mid+1;
+        	else right = mid-1;
+        }
+    	return mid;
+    }
+};

guess_number_higher_or_lower_II/guess_number_higher_or_lower_II.cpp

@@ -0,0 +1,16 @@
+class Solution {
+public:
+    int getMoneyAmount(int n) {
+        vector<vector<int>> dp(n+1, vector<int>(n+1, 0));
+        for (int gap = 1; gap < n; ++gap) {
+        	for (int low = 1; low <= n-gap; ++low) {
+        		int high = low + gap;
+        		dp[low][high] = INT_MAX;
+        		for (int i = low; i < high; ++i) {
+        			dp[low][high] = min(dp[low][high], i + max(dp[low][i-1], dp[i+1][high]));
+        		}
+        	}
+        }
+        return dp[1][n];
+    }
+};

wiggle_subsequence/wiggle_subsequence.cpp

@@ -0,0 +1,21 @@
+class Solution {
+public:
+    int wiggleMaxLength(vector<int>& nums) {
+    	if (nums.size() < 2) return nums.size();
+        int inc_length = 1, dec_length = 1;
+        int pre_inc_v = nums[0], pre_dec_v = nums[0];
+        for (int i = 1; i < nums.size(); ++i) {
+        	if (nums[i] < pre_inc_v && dec_length <= inc_length) {
+        		dec_length = inc_length + 1;
+        		pre_dec_v = nums[i];
+        	}
+        	if (nums[i] > pre_dec_v && inc_length <= dec_length) {
+        		inc_length = dec_length + 1;
+        		pre_inc_v = nums[i];
+        	}
+        	if (nums[i] > pre_inc_v) pre_inc_v = nums[i];
+        	if (nums[i] < pre_dec_v) pre_dec_v = nums[i];
+        }
+        return max(inc_length, dec_length);
+    }
+};