49 lines
910 B
Java
49 lines
910 B
Java
public class NQueens {
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private static int[] b = new int[8];
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private static int s = 0;
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static boolean unsafe(int y) {
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int x = b[y];
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for (int i = 1; i <= y; i++) {
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int t = b[y - i];
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if (t == x ||
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t == x - i ||
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t == x + i) {
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return true;
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}
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}
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return false;
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}
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public static void putboard() {
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System.out.println("\n\nSolution " + (++s));
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for (int y = 0; y < 8; y++) {
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for (int x = 0; x < 8; x++) {
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System.out.print((b[y] == x) ? "|Q" : "|_");
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}
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System.out.println("|");
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}
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}
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public static void main(String[] args) {
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int y = 0;
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b[0] = -1;
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while (y >= 0) {
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do {
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b[y]++;
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} while ((b[y] < 8) && unsafe(y));
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if (b[y] < 8) {
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if (y < 7) {
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b[++y] = -1;
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} else {
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putboard();
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}
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} else {
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y--;
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}
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}
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}
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}
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