依次向后判断即可 #include #include #include using namespace std; bool isSu(int n){ int bound = sqrt(n); for(int i=2;i<=bound;i++){ if(n%i==0){ return false; } } return true; } int main() { int k; while(cin>>k){ int number=2; if(k==1){ cout<<number<<endl; continue; } else { while(k>...