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#include <iostream>

int main() {
   bool prime[101]; /* das Sieb */
   for (int n = 2; n <= 100; ++n) {
      prime[n] = true; /* Annahme zu Beginn */
   }
   for (int n = 2; n <= 100; ++n) {
      if (prime[n]) {
	 std::cout << n << std::endl;
	 if (n * n <= 100) {
	    for (int k = n*n; k <= 100; k += n) {
	       prime[k] = false;
	    }
	 }
      }
   }
}