nixify

2026-06-11 10:59:54 -06:00
commit 8650a71f67
159 changed files with 78653 additions and 0 deletions
@@ -0,0 +1,70 @@
+int printf();
+void *calloc();
+int atoi();
+
+int Q;
+int N;
+int **t;
+
+print() {
+	int x;
+	int y;
+
+	for (y=0; y<Q; y++) {
+		for (x=0; x<Q; x++)
+			if (t[x][y])
+				printf(" Q");
+			else
+				printf(" .");
+		printf("\n");
+	}
+	printf("\n");
+}
+
+chk(int x, int y) {
+	int i;
+	int r;
+
+	for (r=i=0; i<Q; i++) {
+		r = r + t[x][i];
+		r = r + t[i][y];
+		if (x+i < Q & y+i < Q)
+			r = r + t[x+i][y+i];
+		if (x+i < Q & y-i >= 0)
+			r = r + t[x+i][y-i];
+		if (x-i >= 0 & y+i < Q)
+			r = r + t[x-i][y+i];
+		if (x-i >= 0 & y-i >= 0)
+			r = r + t[x-i][y-i];
+	}
+	return r;
+}
+
+go(int y) {
+	int x;
+
+	if (y == Q) {
+		print();
+		N++;
+		return 0;
+	}
+	for (x=0; x<Q; x++)
+		if (chk(x, y) == 0) {
+			t[x][y]++;
+			go(y+1);
+			t[x][y]--;
+		}
+}
+
+main(int ac, void **av) {
+	int i;
+
+	Q = 8;
+	if (ac >= 2)
+		Q = atoi(av[1]);
+	t = calloc(Q, sizeof(int *));
+	for (i=0; i<Q; i++)
+		t[i] = calloc(Q, sizeof(int));
+	go(0);
+	printf("found %d solutions\n", N);
+}