32 lines
880 B
C++
32 lines
880 B
C++
/*************************************************************************
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> File Name: prime_number.cpp
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> Description: prime_number.cpp
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> Author: songtianlun
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> Mail: songtianlun@frytea.com
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> Created Time: 2022-06-23 11:46:18
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************************************************************************/
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#include<iostream>
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#include<math.h>
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using namespace std;
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static int num=100000000;
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int main(){
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bool *array=new bool[num+1];
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array[0]=false;
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array[1]=false;
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for(int i=2;i<=num;i++) array[i]=true;
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int b=int(pow(num,0.5))+1;
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int index=0;
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for(int j=2;j<=b;j++){
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index=2*j;
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while(index<=num){
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array[index]=false;
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index+=j;
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}
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}
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delete array;
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cout<<endl<<"===========Done!==========="<<endl;
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return 0;
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}
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