Language: C

    /* C++14 (Clang 3.8.0) for AtCoder */
     
    #include <iostream>
    #include <vector>
    #include <string>
    // #include <cmath>
    // #include <math.h>
    // #include <map>
    // #include <algorithm>
     
    namespace AtCoder {
    	using Str = std::vector<std::string>;
    	using Num = std::vector<int>;
    	using BigNum = std::vector<long long>;
     
    	class InputData {
    	public:
    		void getInput(void);
    		void skipInput(void);
    		Str getStr(void);
    		Num getNum(void);
    		BigNum getBigNum(void);
    	private:
    		Str str;
    		Num num;
    		BigNum bNum;
    	};
    	Str AtCoder::InputData::getStr(void) {
    		return this->str;
    	}
    	Num AtCoder::InputData::getNum(void) {
    		return this->num;
    	}
    	BigNum AtCoder::InputData::getBigNum(void) {
    		return this->bNum;
    	}
    	void AtCoder::InputData::skipInput(void) {
    		std::string buf = "";
    		std::getline(std::cin, buf);
    	}
    	void AtCoder::InputData::getInput(void) {
    		this->str.clear();
    		this->num.clear();
    		this->bNum.clear();
     
    		std::string buf = "", row = "";
    		std::getline(std::cin, buf);
    		for (unsigned int i = 0; i < buf.size(); i++) {
    			if (' ' == buf[i]) {
    				this->str.push_back(row);
    				this->num.push_back(std::atoi(row.c_str()));
    				this->bNum.push_back(std::atoll(row.c_str()));
    				row = "";
    			} else {
    				row += buf[i];
    			}
    		}
    		this->str.push_back(row);
    		this->num.push_back(std::atoi(row.c_str()));
    		this->bNum.push_back(std::atoll(row.c_str()));
    	}
     
    	class Ans {
    	public:
    		void showResult(void);
    		void increment(void);
    		void increment(long long);
    		void decrement(void);
    		void decrement(long long);
    		long long getResult(void);
    	private:
    		long long result;
    	};
    	void Ans::showResult(void) {
    		printf("%lld\n", this->result);
    	}
    	void AtCoder::Ans::increment(void) {
    		this->result++;
    	}
    	void AtCoder::Ans::increment(long long value) {
    		this->result += value;
    	}
    	void AtCoder::Ans::decrement(void) {
    		this->result--;
    	}
    	void AtCoder::Ans::decrement(long long value) {
    		this->result -= value;
    	}
    	long long AtCoder::Ans::getResult(void) {
    		return this->result;
    	}
     
    	void exp(std::string* str,  Str* newStr) {
    		std::string pre = *str;
    		newStr->clear();
    		for (unsigned int i = 0; i < pre.length(); i++) {
    			newStr->push_back(pre.substr(i, 1));
    		}
    	}
    }
     
    int main(void) {
     
    	AtCoder::InputData* data = new AtCoder::InputData();
    	data->getInput();
     
    	const int num = data->getNum()[0];
     
    	AtCoder::Ans* ans = new AtCoder::Ans();
     
    	for (int i = 0; i < num; i++) {
    		int buf = i + 1;
    		if (0 == buf % 5 ||
    			0 == buf % 3) {
    			continue;
    		} else {
    			ans->increment(buf);
    		}
    	}
     
    	ans->showResult();
     
    	delete(ans);
    	delete(data);
     
    	return 0;
    }

Compiler output:
main.c:3:14: fatal error: iostream: No such file or directory
    3 |     #include <iostream>
      |              ^~~~~~~~~~
compilation terminated.