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过了贴代码攒rp,有注释有真相#include <iostream> #include <cstdlib> #include <cstdio> #include <cstring> #define max 10001 #define sum 1230//10000以下总共有1229个素数 using namespace std; int prime [sum];//这个数组用于存放素数 int num(int n)//用于计算可能的组合的个数。 { int a=prime[1],ans=0;//ans为个数,a为当前计算的和,n为目标值 for(int i=1,j=2;j<sum&&prime[i]<=n&&i<=j;i++) { a-=prime[i-1]; while(a<n&&j<sum) { a+=prime[j++]; } if(a==n){ans++;} } return ans; } int main() { bool * data=new bool [max];//双下标法找素数 memset(data,true,max*sizeof(bool)); data[0]=false;data[1]=false;prime[0]=0; for(int i=2,j=1,k;i<max;i++) { if(!data[i]){continue;} prime[j++]=i;//记录素数 for(k=(i<<1);k<max;k+=i){data[k]=false;} } delete(data);//不用了就释放内存 int n; while(cin>>n) { if(!n){break;} cout<<num(n)<<endl; } return 0; } Followed by:
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