#include <iterator>
#include <algorithm>
 
    template<typename Iterator, typename Lambda, typename Counter>
    Iterator find_if_nth( Iterator begin, Iterator end, Lambda closure, Counter n ) {
      typedef typename std::iterator_traits<Iterator>::reference Tref;
      return std::find_if(begin, end, [&n,&closure](Tref x) {
        return closure(x) && !(--n);
      });
    }
#include <vector>
#include <iostream>
int main() {
    std::string v = "1 2 3 4 5 6 7  8";
    auto it = find_if_nth( v.begin(), v.end(), [](auto x){return x==' ';}, 2);
    std::cout << "2nd 2 is at offset " << (it-v.begin()) << " with value [" << *it << "]\n";
}

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