30 lines
515 B
C++
30 lines
515 B
C++
#include "fcpp.hh"
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int main ()
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{
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const int n = 500000;
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bool prim[n];
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// Initialisierung
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prim[0] = false;
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prim[1] = false;
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for (int i=2; i<n; i=i+1)
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prim[i] = true;
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// Sieb
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for (int i=2; i<=sqrt((double) n); i=i+1)
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if (prim[i])
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for (int j=2*i; j<n; j=j+i)
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prim[j] = false;
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// Ausgabe
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int m=0;
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for (int i=0; i<n; i=i+1)
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if (prim[i])
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m = m+1;
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print("Anzahl Primzahlen:");
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print(m);
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return 0;
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}
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