这就是您可以做的事情（为了简洁起见，省略了输入验证）。

#include <vector>
#include <iterator>

// You have to pass values as const (you promise not to change the content)
// and by reference (the &) to avoid copying the whole vector.
// since you should not pass iterators around just use an index into the vector.
std::vector<int> copy_all_but_value_at_index(const std::vector<int>& values,std::size_t index)
{
    // use on fo vector's constructors to your advantage.
    // copy the first part of the vector to the result
    std::vector<int> retval{ values.begin(), values.begin() + index  };

    // then insert the rest of the values at the end
    retval.insert(retval.end(), values.begin() + index + 1, values.end());
    return retval;
}

int main()
{
    auto result = copy_all_but_value_at_index({ 1,2,3,4,5 }, 3ul);
    return 0;
}