Submission #1749267

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Source Code Expand

#include<iostream>
#include<cmath>

double X;

using namespace std;

int main() {
	cin >> X;
	cout << long long(ceil((-1 + sqrt(1 + 8 * X)) / 2)) << endl;
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:10:10: error: expected primary-expression before ‘long’
  cout << long long(ceil((-1 + sqrt(1 + 8 * X)) / 2)) << endl;
          ^