adjacent_find

示例：

#include<iostream>
using namespace std;
#include<vector>
#include<algorithm>
void test01()
{
	vector<int>v;

	v.push_back(1);
	v.push_back(2);
	v.push_back(1);
	v.push_back(3);
	v.push_back(1);
	v.push_back(4);
	v.push_back(1);
	v.push_back(3);
	v.push_back(3);

	vector<int>::iterator pos = adjacent_find(v.begin(), v.end());

	if (pos == v.end())
	{
		cout << "找不到相邻重复元素" << endl;
	}
	else
	{
		cout << "找到相邻重复元素为" << *pos << endl;
	}
}
int main()
{
	test01();
	return 0;
}

总结：如果面试题中要求查找相邻重复元素，可以使用STL中的abjacent算法