用的根号筛

#include <bits/stdc++.h> using namespace std; int a[101]; bool pdssh(int a) { if(a<2) return false; if(a2) return true; for(int i=2;i<=sqrt(a);i++) if(a%i0) return false; return true; } int main(){ int n,m,x,s=0; cin>>n>>m; for(int i=1;i<=n;i++) cin>>a[i]; for(int i=1;i<=m;i++) { cin>>x; if(pdssh(a[x])==true) s+=a[x]; } cout<<s<<endl; return 0; }

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n, m = map(int, input().split()) cards = list(map(int, input().split())) indices = list(map(int, input().split())) def is_prime(y): if y < 2: return False for i in range(2, int(y**0.5) + 1): if y % i == 0: return False return True selected_cards = [cards[i-1] for i in indices] prime_sum = sum(card for card in selected_cards if is_prime(card)) print(prime_sum)

def is_prime(num): if num <= 1: return False for i in range(2, int(num**0.5) + 1): if num % i == 0: return False return True n, m = map(int, input().split()) cards = list(map(int, input().split())) selected_indices = list(map(int, input().split())) selected_cards = [cards[i-1] for i in selected_indices] prime_sum = sum(card for card in selected_cards if is_prime(card)) print(prime_sum)

整体还好 #include<bits/stdc++.h> using namespace std; int main(){ int n,m; cin>>n>>m; int s[105]; for(int i=1;i<=n;i++){ cin>>s[i]; } int c,num=0; for(int i=1;i<=m;i++){ cin>>c; int g=0; for(int j=2;j<s[c];j++){ if(s[c]%j0){ g=1; } } if(g0){ num+=s[c]; } } cout<<num; return 0; }

加粗文本 #include<iostream> #include<cmath> using namespace std; bool ifprime(int x){ if(x<2){ return false; } int m=int(sqrt(x))+1; for(int i=2;i<m;i++){ if(x%i==0){ return false; } } return true; } int main(){ int n,m,sum=0; cin>>n>>m; n++; int a[n],b[m]; for(int i=1;i<n;i++){ cin>>a[i]; } int temp; for(int i=0;i<m;i++){ cin>>b[i]; if(ifprime(a[b[i]])){ sum+=a[b[i]]; } } cout<<sum; return 0; }

#include <iostream> #include <vector> using namespace std; bool isPrime(int num) { if (num <= 1) return false; if (num == 2 || num == 3) return true; if (num % 2 == 0 || num % 3 == 0) return false; for (int i = 5; i * i <= num; i += 6) { if (num % i == 0 || num % (i + 2) == 0) return false; } return true; } int main() { int n, m; cin >> n >> m; }

#include<bits/stdc++.h> using namespace std; int main(){ int n,m; cin>>n>>m; int s[105]; for(int i=1;i<=n;i++){ cin>>s[i]; } int c,num=0; for(int i=1;i<=m;i++){ cin>>c; int g=0; for(int j=2;j<s[c];j++){ if(s[c]%j0){ g=1; } } if(g0){ num+=s[c]; } } cout<<num; return 0; }