#include <iostream> using namespace std; int main(){ int a,s = 0; cin >> a; if (a % 3 == 0) cout << "3 "; else s += 1; if (a % 5 == 0) cout << "5 "; else s += 1; if (a % 7 == 0) cout << "7 "; else s += 1; if (s == 3) cout << "n"; return 0; }

#include<bits/stdc++.h> using namespace std; int main(){ int x; cin>>x; if(x%30){ cout<<3<<" "; }if(x%50){ cout<<5<<" "; }if(x%7==0){ cout<<7<<" "; }if(x%3!=0&&x%5!=0&&x%7!=0){ cout<<"n"; } return 0; }

#include <iostream> using namespace std; int main() { int n; cin >> n; // 输入整数 }

（题解如下） #include<iostream> using namespace std; int main () { int n; cin >>n; if(n%70&&n%50&&n%30) { cout<<3<<" "<<5<<" "<<7; } else if(n%70&&n%50&&n%3!=0) { cout<<5<<" "<<7; } else if(n%7!=0&&n%50&&n%30) { cout<<3<<" "<<5; } else if(n%70&&n%5!=0&&n%30) { cout<<3<<" "<<7; } else if(n%70&&n%5!=0&&n%3!=0) { cout<<7; } else if(n%7!=0&&n%50&&n%3!=0) { cout<<5; } else if(n%7!=0&&n%5!=0&&n%30) { cout<<3; } else if(n%7!=0&&n%5!=0&&n%3!=0) { cout<<"n"; } } 不需要什么技术，就是纯废手。（如果想要不废的可以看看前面几个大佬的）

#include <bits/stdc++.h> using namespace std; int main(){ int a; cin>>a; if(a%3 = =0)cout<<'3'<<' '; if(a%5 = =0)cout<<'5'<<' '; if(a%7==0)cout<<'7'; if(a%3!=0&&a%5!=0&&a%7!=0)cout<<'n'; return 0; }

#include<iostream> using namespace std; int main(){ int n; cin>>n; if(n%30){ cout<<"3"<<" "; } if(n%50){ cout<<"5"<<" "; } if(n%7==0){ cout<<"7"<<" "; } if(n%3!=0&&n%5!=0&&n%7!=0){ cout<<"n"; } return 0; }

#include<bits/stdc++.h> using namespace std; int main(){ int a; cin>>a; if(a%30 && a%50 && a%70)cout<<"3 5 7"; else if(a%30 && a%50)cout<<"3 5"; else if(a%30 && a%70)cout<<"3 7"; else if(a%50 && a%70)cout<<"5 7"; else if(a%50)cout<<5; else if(a%30)cout<<3; else if(a%70)cout<<7; else cout<<'n'; return 0; }

#include<iostream> using namespace std; int main() { int n; cin>>n; if(n%30) cout<<"3"<<" "; if(n%50) cout<<"5"<<" "; if(n%7==0) cout<<"7"<<" "; if(n%3!=0&&n%5!=0&&n%7!=0) cout<<"n"; return 0; }

真简单