How to find out if an item is present in an std vector

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All I want to do is see if an element in the vector exists or not, so I can deal with each instance individually.
May 26, 2022 in Others by Nicholas
• 7,760 points
563 views

1 answer to this question.

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The most straightforward solution is to count the total number of elements in the vector that have the specified value. 

If the count is greater than zero, we've found our element. 

This is simple to accomplish with the std::count function.

#include <iostream>

#include <vector>

#include <algorithm>


int main()

{

    std::vector<int> v = { 4, 7, 5, 2, 6, 9 };

    int key = 6;


    if (std::count(v.begin(), v.end(), key)) {

        std::cout << "Element found";

    }

    else {

        std::cout << "Element not found";

    }


    return 0;

}
answered May 27, 2022 by Damon
• 4,960 points

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