#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;
int main() {
srand((unsigned)time(0));
int num = 1000000;
double sumOfTriggers = 0.0;
for (int i = 0; i < num; i++) {
int noFailure = 1;
while (noFailure) {
noFailure = rand() % 2;
sumOfTriggers += noFailure ? 1 : 0;
}
}
cout << (sumOfTriggers / num) << "\n";
return 0;
}
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