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GcdProblem.java
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GcdProblem.java
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import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.StringTokenizer;
public class GcdProblem {
public static void main(String[] args) {
// a + b + c = n
// gcd(a, b) = c
// greatest common divisor
// find smallest divisor
//
// DISTINCT
FastReader fr = new FastReader();
int ts = fr.nextInt();
List<Long> primes = getPrimes((long) Math.pow(10, 9));
for (int t = 0; t < ts; t++) {
long n = fr.nextLong();
// for (long n = 10; n < Math.pow(10, 9); n++) {
long a = 1;
long b = 1;
long c = 1;
for (int i = 0; i < primes.size() && primes.get(i) < n - primes.get(i) - 1; i++) {
long potentialB = n - primes.get(i) - 1;
if (potentialB % primes.get(i) > 0) {
a = primes.get(i);
b = potentialB;
break;
}
}
// a, n - 3, 1
// find the first prime that does not divide n - p
// 1, 1, 1
// 2, 2, 2
// 2, 3, 1
// 3, 3, 3
//
// pj1^j1 * ... * pjk^jk, pm1^m1 * ... * pmk^mk
// the overlap has to be equal to c
// 1, 1, 1
// get
if (a + b + c != n || (a == b || b == c)) {
System.out.println("WRONG for n: " + n);
System.out.println(a + " " + b + " " + c);
} else {
System.out.println(a + " " + b + " " + c);
}
}
}
public static List<Long> getPrimes(long n) {
List<Long> primes = new ArrayList<>();
HashSet<Long> nonPrimes = new HashSet<>();
long length = (long) Math.sqrt(n);
for (long number = 2; number <= length; number++) {
if (!nonPrimes.contains(number)) {
// is prime
for (int i = 0; number * number + i * number < length; i++) {
nonPrimes.add(number * number + i * number);
}
}
}
for (long i = 2; i < length; i++) {
if (!nonPrimes.contains(i)) {
primes.add(i);
}
}
return primes;
}
/** HELPER */
static class FastReader {
BufferedReader br;
StringTokenizer st;
public FastReader()
{
br = new BufferedReader(
new InputStreamReader(System.in));
}
int[] nextLineAsIntArray(int n) {
int[] result = new int[n];
for (int i = 0; i < n; i++) {
result[i] = nextInt();
}
return result;
}
long[] nextLineAsLongArray(int n) {
long[] result = new long[n];
for (int i = 0; i < n; i++) {
result[i] = nextLong();
}
return result;
}
String next()
{
while (st == null || !st.hasMoreElements()) {
try {
st = new StringTokenizer(br.readLine());
}
catch (IOException e) {
e.printStackTrace();
}
}
return st.nextToken();
}
int nextInt() { return Integer.parseInt(next()); }
long nextLong() { return Long.parseLong(next()); }
double nextDouble()
{
return Double.parseDouble(next());
}
String nextLine()
{
String str = "";
try {
str = br.readLine();
}
catch (IOException e) {
e.printStackTrace();
}
return str;
}
}
}