C++ sort a vector of struct, but one element is missing [closed]

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I have a struct (name, val1, val2) and want to sort by val2, but how come it is always missing one element? Below is my code:

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

int main()
{
    struct sub
    {
        std::string name;
        int val1; 
        int val2; 
    };

    std::vector< sub > vec; 
    vec.push_back( { "first", 2, 3 } );
    vec.push_back( { "second", 2, 1 } );
    vec.push_back( { "Third", 1, 5 } );
    vec.push_back( { "Forth", 1, 8 } );
    vec.push_back( { "Fifth", 1, 10 } );
     
    std::sort( vec.begin(), vec.end(), []( const sub & a, const sub & b )
    {
        return a.val2 > b.val2;
    } );

    for ( auto vec1 = vec.begin(); vec1 != vec.end(); ++vec1 )
    {
        std::cout << vec1->name << std::endl; 
    }

    return 0;
}

For result, I got:

Forth
Third
first
second

Why is Fifth not showing ?