Update 162_Find_Peak_Element.cpp

Author: xliu45

C/162_Find_Peak_Element.cpp

@@ -1,55 +1,52 @@
-//A peak element is an element that is greater than its neighbors.
-//
-//Given an input array where num[i] ≠ num[i+1], find a peak element and return its index.
-//
-//The array may contain multiple peaks, in that case return the index to any one of the peaks is fine.
-//
-//You may imagine that num[-1] = num[n] = -∞.
-//
-//For example, in array [1, 2, 3, 1], 3 is a peak element and your function should return the index number 2.
-//
-//Author: Xinyu Liu
+/*
+A peak element is an element that is greater than its neighbors.
+Given an input array where num[i] ≠ num[i+1], find a peak element and return its index.
+The array may contain multiple peaks, in that case return the index to any one of the peaks is fine.
+You may imagine that num[-1] = num[n] = -∞.
+
+Example:
+in array [1, 2, 3, 1], 3 is a peak element and your function should return the index number 2.
+
+Tag: Array, Binary Search
+
+Author: Xinyu Liu
+*/
 
 #include <iostream>
 #include <vector>
 using namespace std;
 
-
-
 class Solution {
 
 public:
-	int findPeakElement(vector<int>& nums) {
-		int sz = nums.size();
-		if (sz == 1)
-			return 0;
-		if (nums.at(0)>nums.at(1)) 
-			return 0;
-		if (nums.at(sz-1)>nums.at(sz-2)) 
-			return sz-1;
-
-		for(int i =1; i<nums.size();i++)
-		{
-			
-			if (nums.at(i-1)<nums.at(i)&nums.at(i)>nums.at(i+1))
-				return i;
-		}
-		return -1;
-
+    int findPeakElement(vector<int>& nums) {
+        int sz = nums.size();
+	if (sz == 1)
+	    return 0;
+	if (nums.at(0) > nums.at(1)) 
+	    return 0;
+	if (nums.at(sz-1) > nums.at(sz-2)) 
+	    return sz-1;
+
+	for(int i = 1; i < nums.size(); i++)
+	{
+	    if (nums.at(i-1) < nums.at(i) & nums.at(i) > nums.at(i+1))
+	        return i;
 	}
+	return -1;
+    }
 };
 
-void main(){
-
+void main(int argc, char ** argv){
 
-	// Initialize vector
-	int myints[] = {1,2,3,4,3};
-	int index;
-	std::vector<int> test (myints, myints + sizeof(myints) / sizeof(int) );
+    // Initialize vector
+    int myints[] = {1,2,3,4,3};
+    int index;
+    std::vector<int> test (myints, myints + sizeof(myints) / sizeof(int) );
 
-	Solution sol;
-	index = sol.findPeakElement (test);
+    Solution sol;
+    index = sol.findPeakElement (test);
 
-	printf("%i \n",index);
+    printf("%i \n",index);
 
 }