c++ 找到一个元素和它在向量的位置

[c++]代码库

// 找到一个元素和它在向量的位置

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
	// A dynamic array of integers
	vector<int> vecIntegerArray;

	// Insert sample integers into the array
	vecIntegerArray.push_back(50);
	vecIntegerArray.push_back(2991);
	vecIntegerArray.push_back(23);
	vecIntegerArray.push_back(9999);

	cout << "The contents of the vector are: " << endl;

	// Walk the vector and read values using an iterator
	vector<int>::iterator iArrayWalker = vecIntegerArray.begin();

	while (iArrayWalker != vecIntegerArray.end()) {
		// Write the value to the screen
		cout << *iArrayWalker << endl;

		// Increment the iterator to access the next element
		++iArrayWalker;
	}

	// Find an element (say 2991) in the array using the 'find' algorithm...
	vector<int>::iterator iElement = find(vecIntegerArray.begin(),
			vecIntegerArray.end(), 2991);

	// Check if value was found
	if (iElement != vecIntegerArray.end()) {
		// Value was found... Determine position in the array:
		int nPosition = distance(vecIntegerArray.begin(), iElement);
		cout << "Value " << *iElement;
		cout << " found in the vector at position: " << nPosition << endl;
	}

	return 0;
}