A reversible prime in any number system is a prime whose "reverse" in that number system is also a prime. For example in the decimal system 73 is a reversible prime because its reverse 37 is also a prime.
Now given any two positive integers N (< 105) and D (1 < D <= 10), you are supposed to tell if N is a reversible prime with radix D.
Input Specification:
The input file consists of several test cases. Each case occupies a line which contains two integers N and D. The input is finished by a negative N.
Output Specification:
For each test case, print in one line "Yes" if N is a reversible prime with radix D, or "No" if not.
Sample Input:73 1023 223 10-2Sample Output:YesYesNo#include <iostream>#include <algorithm>#include <queue>using namespace std;bool isPrime(int x) {if(x < 2) {return false;}if(x == 2 || x == 3) {return true;}for(int i=2; i*i<=x; i++) {if(x % i == 0) {return false;}}return true;}int main() {int n, d;while(cin>>n) {if(n < 0) {break;} else {cin>>d;if(isPrime(n)) {queue<int> q;while(n!=0) {q.push(n%d);n /= d;}int reverse = 0;while(!q.empty()) {reverse=reverse*d;reverse=reverse+q.front();q.pop();}if(isPrime(reverse)) {cout<<"Yes"<<endl;} else {cout<<"No"<<endl;}} else {cout<<"No"<<endl;}}}return 0;}
，世界上那些最容易的事情中，拖延时间最不费力。
