#include <iostream>
using namespace std;
 
const int MAX_LENGTH = 10;
const int TEN = 10;
 
int sameDig(int n, int v[]) {
	int counterSameDig = 0;
		for (int i = 1; i <= n; ++i) {
			//while(v[i]) {
				if ((v[i] % TEN == v[i] / TEN % TEN && v[i] / TEN % TEN  == v[i] / (TEN * TEN)) && v[i] < (TEN * TEN * TEN) ) {
					++counterSameDig;	
				}
			//}
	} 
	return counterSameDig;
}
 
int main() {
	int n, v[MAX_LENGTH + 1];
	cin >> n;
	for (int i = 1; i <= n; ++i) {
		cin >> v[i];
	}
	cout << sameDig(n, v);
	return 0;
}

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