素数筛然后前缀和
看代码
#include<cstdio>
#include<vector>
#include<cstring>
#include<map>
#define REP(i, a, b) for(int i = (a); i < (b); i++)
using namespace std;const int MAXN = 11234;
bool is_prime[MAXN];
vector<int> prime;
int a[MAXN];
map<int, int> f;void init()
{memset(is_prime, true, sizeof(is_prime));is_prime[0] = is_prime[1] = false;REP(i, 2, MAXN){if(is_prime[i]) prime.push_back(i);REP(j, 0, prime.size()){if(i * prime[j] >= MAXN) break;is_prime[i * prime[j]] = false;if(i % prime[j] == 0) break;}}
}int main()
{init();a[0] = prime[0];REP(i, 1, prime.size())a[i] = a[i-1] + prime[i];REP(i, 0, prime.size())REP(j, i, prime.size()){if(i == 0) f[a[j]]++;else f[a[j] - a[i-1]]++;}int n;while(~scanf("%d", &n) && n)printf("%d\n", f[n]);return 0;
}