B1013 數素數
阿新 • • 發佈:2017-10-10
+= class bsp find urn each include break cout
#include<iostream> using namespace std; const int MAXN = 1000000; int prime[MAXN]; int num = 0; bool p[MAXN] = { 0 }; void find_prime(int n) { for (int i = 2; i<MAXN; i++) { if (p[i] == false) { prime[num++] = i; if (num >= n) break; for (int j = i + i; j<MAXN; j +=i)//j<maxn,not j<=n { p[j] = true; } } } } int main() { int count = 0; int m, n; cin >> m >> n; find_prime(n); for (int i = m; i<n + 1; i++) { cout << prime[i - 1];//coz array index begin with 0,so the Mth number,which index is m-1 count++; if (count % 10 != 0 && i<n)//10 numbers of each line, good idea! cout << " "; else cout << endl; } return 0; }
B1013 數素數