poj 2739
打一个素数表，发现10000以内的素数个数在1300个之内，直接暴力即可。
1 #include<iostream> 2 #include<cstdio> 3 #include<cstdlib> 4 #include<cstring> 5 #include<string> 6 #include<queue> 7 #include<algorithm> 8 #include<map> 9 #include<iomanip> 10 #include<climits> 11 #include<string.h> 12 #include<numeric> 13 #include<cmath> 14 #include<stdlib.h> 15 #include<vector> 16 #include<stack> 17 #include<set> 18 #define INF 1e7 19 #define MAXN 100010 20 #define maxn 1000010 21 #define Mod 1000007 22 #define N 1010 23 using namespace std; 24 typedef long long LL; 25 26 int prime[11000]; 27 int vis[11000]; 28 void run() 29 { 30 int k = 1; 31 for (int i = 2; i <= 10000; ++i) 32 if (!vis[i]) { 33 prime[k++] = i; 34 for (int j = i*i; j <= 10000; j += i) 35 vis[j] = 1; 36 } 37 /*for (int i = 1; i < 1300; ++i) 38 cout << prime[i] << " "; 39 cout << endl;*/ 40 } 41 42 int n; 43 int cnt; 44 45 void deal(int tmp) 46 { 47 for (int i = 1; i < 1300 && prime[i]; ++i) { 48 int left = tmp; 49 if (tmp < prime[i]) continue; 50 for (int j = i ; j < 1300 && prime[j]; ++j) { 51 left -= prime[j]; 52 if (left < 0) break; 53 if (left == 0) cnt++; 54 } 55 56 } 57 } 58 59 int main() 60 { 61 run(); 62 while (cin >> n,n) { 63 cnt = 0; 64 deal(n); 65 printf("%d\n",cnt); 66 } 67 return 0; 68 }
