How to point the iterator to an element in a vector which is greater than or equal to a target number

user_16958065 0
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For example, I have a vector as v=[7,4,5,10,13]. Here my target number is 6. I am first sorting the vector with:

sort(v.begin(), v.end());

Now my output would be [4,5,7,10,13]. After this, I want to print the numbers greater than or equal to '6', which will give me output as [7,10,13].

What's a convenient way in C++ to perform this task?

vector c++
3 Answers

Use std::upper_bound:

#include <algorithm>
#include <vector>
#include <iostream>

int main()
{
   std::vector<int> v = {7,4,5,10,13};
   std::sort(v.begin(), v.end());
   auto iter = std::upper_bound(v.begin(), v.end(), 6);
   for (; iter != v.end(); ++iter)
     std::cout << *iter << " ";
}

Output:

7 10 13
user_31333160

This is my quick solution

std::vector<int> v = {7,4,5,10,13};
std::sort(v.begin(), v.end());
std::copy_if(v.begin(), v.end(), std::ostream_iterator<int>(std::cout, " "), 
[](int a){ return a > 6;})
user_152624890

Or if you compiler already supports it use 

#include <algorithm>
#include <ranges>
#include <vector>
#include <iostream>

auto larger_then_6 = [](int i) { return i > 6; };

int main()
{
    std::vector<int> v = { 7,4,5,10,13 };
    std::sort(v.begin(), v.end());

    for (auto value : v | std::views::filter(larger_then_6))
    {
        std::cout << value << " ";
    }

    std::cout << std::endl;
}
user_166495500
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