Implement puzzle generation

main.c

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) Camden Dixie O'Brien
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+#include "puzz.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/time.h>
+
+int main(void)
+{
+	struct timeval tv;
+	if (gettimeofday(&tv, NULL) != 0) {
+		perror("Failed to get time");
+		exit(1);
+	}
+	srand(tv.tv_usec);
+
+	gen();
+	print();
+
+	return 0;
+}

puzz.c

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) Camden Dixie O'Brien
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+#include "puzz.h"
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static puzz_t soln;
+
+void gen(void)
+{
+	memset(soln, 0, sizeof(soln));
+
+	for (int i = 0; i < NMINES; ++i) {
+		int x, y;
+		do {
+			x = rand() % WIDTH;
+			y = rand() % HEIGHT;
+		} while (soln[x][y] == MINE);
+		soln[x][y] = MINE;
+	}
+
+	for (int y = 0; y < HEIGHT; ++y) {
+		for (int x = 0; x < WIDTH; ++x) {
+			if (soln[x][y] == MINE)
+				continue;
+			for (int yp = y - 1; yp < y + 2; ++yp) {
+				for (int xp = x - 1; xp < x + 2; ++xp) {
+					if (xp < 0 || xp >= WIDTH || yp < 0 || yp >= HEIGHT)
+						continue;
+					soln[x][y] += soln[xp][yp] == MINE ? 1 : 0;
+				}
+			}
+		}
+	}
+}
+
+void print(void)
+{
+	for (int y = 0; y < HEIGHT; ++y) {
+		for (int x = 0; x < WIDTH; ++x)
+			putchar(soln[x][y] == MINE ? 'x' : '0' + soln[x][y]);
+		putchar('\n');
+	}
+}

puzz.h

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) Camden Dixie O'Brien
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+#ifndef PUZZ_H
+#define PUZZ_H
+
+#define WIDTH 10
+#define HEIGHT 10
+#define NMINES 10
+
+#include <stdint.h>
+
+enum { MINE = 0xff };
+
+typedef uint8_t puzz_t[WIDTH][HEIGHT];
+
+void gen(void);
+void print(void);
+
+#endif