Nyoj 24 prime number distance problem

Prime Number distance problem time limit: 3000 MS | memory limit: 65535 kb difficulty: 2

Description

Now you are given some numbers. You need to write a program to output the adjacent prime numbers of these integers and their length. If there is a prime number with an equal-distance length between the left and right, the value on the left and the corresponding distance are output.
If the input integer itself is a prime number, the output is the prime number and the distance is 0.

Input

The first line shows the number of test data groups N (0 <n <= 10000)
Each row in the next n Rows has an integer m (0 <m <1000000 ),

Output

Each row outputs two integers a B.
A Indicates the prime number closest to the test data, and B indicates the distance between them.

Sample Input

36810

Sample output

5 17 111 1

Java code:

/** Search for the smallest prime number distance, priority analysis: * 1. Determine whether the input is a prime number, is a prime number output ** 2. Judge the nearest prime number on the left * 3. Judge the nearest prime number on the right ** Special Case, note that number 1 is not a prime number **/package Org. OJ; import Java. util. strong; public class main {// determine the prime number private Boolean is_prime (int x) {If (x> 1) {If (x <4) {// returns true for the prime number 2 and 3 ;} else {for (INT I = 2; I <= math. SQRT (x); I + = 1) {If (X % I = 0) return false;} return true ;}} return false ;} public static void main (string [] ARGs) {custom scan = new custom (system. in); main Nyo J = new main (); int n = scan. nextint (); // number of groups for (INT I = 0; I <n; I ++) {int M = scan. nextint (); If (M <0) break; If (nyoj. is_prime (M) {system. out. println (m + "" + 0); continue;} // distance int d = (M % 2 = 0 )? 1:0; // special case: 1 is not a prime number if (M = 1) {system. out. println ("2 1");} else {While (true) {int min = m-D; int max = m + D; If (nyoj. is_prime (min) {system. out. println (min + "" + d); break;} else {If (nyoj. is_prime (max) {system. out. println (MAX + "" + d); break ;}} D + = 2 ;}} scan. close ();}}

Nyoj 24 prime number distance problem