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其实这道题感觉可以和2140类比,我的是先建立一个查询表,再直接搜In Reply To:做了好多关于素数的题,这个算是比较综合的,呵呵~~~~ Posted by:xiaoyuanwang at 2007-05-04 16:27:23 #include<stdio.h>
#include<math.h>
long p[1500][1500];
bool is_prime(long n)
{
long i;
for(i=2;i<=sqrt(n);i++)
if(n%i==0)
return 0;
return 1;
}
void build_p()
{
int i,j;
int step=1;
for(i=2;step<1500&&i<=20000;i++)
if(is_prime(i))p[1][step++]=i;
for(i=2;i<1300;i++)
for(j=1;j<1300;j++)
p[i][j]=p[i-1][j]+p[1][i+j-1];
}
void solve(int n)
{
int cnt,i,j;
i=j=1;
cnt=0;
for(i=1;i<1300;i++)
for(j=1;j<1300;j++)
if(p[i][j]==n)cnt++;
printf("%d\n",cnt);
}
int main()
{
int n;
build_p();
while(scanf("%d",&n),n!=0)
solve(n);
return 0;
}
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