feat: add 2nd ts solution to lc problem: No.0959

Author: rain84

solution/0900-0999/0959.Regions Cut By Slashes/README.md

@@ -390,4 +390,90 @@ function regionsBySlashes(grid) {
 
 <!-- solution:end -->
 
+<!-- solution:start -->
+
+### Solution 2: DFS
+
+<!-- tabs:start -->
+
+#### TypeScript
+
+```ts
+function regionsBySlashes(grid: string[]): number {
+    const createGraph = () => {
+        const n = grid.length;
+        const g = Array.from({ length: n * 2 }, () => Array(n * 2).fill(0));
+
+        for (let i = 0; i < n; i++) {
+            for (let j = 0; j < n; j++) {
+                const [y, x] = [i * 2, j * 2];
+
+                switch (grid[i][j]) {
+                    case '/':
+                        g[y][x] = g[y + 1][x + 1] = 0;
+                        g[y][x + 1] = g[y + 1][x] = 1;
+                        break;
+
+                    case '\\':
+                        g[y][x] = g[y + 1][x + 1] = 2;
+                        g[y][x + 1] = g[y + 1][x] = 0;
+                        break;
+
+                    default:
+                        g[y][x] = g[y][x + 1] = g[y + 1][x] = g[y + 1][x + 1] = 0;
+                        break;
+                }
+            }
+        }
+
+        return g;
+    };
+
+    const isValid = (x: number) => 0 <= x && x < n;
+    const dfs = (i: number, j: number) => {
+        if (!isValid(i) || !isValid(j) || g[i][j]) return;
+
+        g[i][j] = -1;
+        const dirs = [-1, 0, 1, 0, -1];
+        const neighbours: number[] = [];
+
+        for (let d = 0; d < 4; d++) {
+            const [y, x] = [i + dirs[d], j + dirs[d + 1]];
+
+            if (isValid(y) && isValid(x)) {
+                dfs(y, x);
+                neighbours.push(g[y][x]);
+            } else {
+                neighbours.push(-1);
+            }
+        }
+
+        const [top, right, bottom, left] = neighbours;
+        if (top === 1 && right === 1) dfs(i - 1, j + 1);
+        if (bottom === 1 && left === 1) dfs(i + 1, j - 1);
+        if (top === 2 && left === 2) dfs(i - 1, j - 1);
+        if (bottom === 2 && right === 2) dfs(i + 1, j + 1);
+    };
+
+    const g = createGraph();
+    const n = g.length;
+    let res = 0;
+
+    for (let i = 0; i < n; i++) {
+        for (let j = 0; j < n; j++) {
+            if (g[i][j] === 0) {
+                dfs(i, j);
+                res++;
+            }
+        }
+    }
+
+    return res;
+}
+```
+
+<!-- tabs:end -->
+
+<!-- solution:end -->
+
 <!-- problem:end -->

solution/0900-0999/0959.Regions Cut By Slashes/README_EN.md

@@ -65,7 +65,7 @@ tags:
 
 <!-- solution:start -->
 
-### Solution 1
+### Solution 1: Union-Find
 
 <!-- tabs:start -->
 
@@ -380,4 +380,90 @@ function regionsBySlashes(grid) {
 
 <!-- solution:end -->
 
+<!-- solution:start -->
+
+### Solution 2: DFS
+
+<!-- tabs:start -->
+
+#### TypeScript
+
+```ts
+function regionsBySlashes(grid: string[]): number {
+    const createGraph = () => {
+        const n = grid.length;
+        const g = Array.from({ length: n * 2 }, () => Array(n * 2).fill(0));
+
+        for (let i = 0; i < n; i++) {
+            for (let j = 0; j < n; j++) {
+                const [y, x] = [i * 2, j * 2];
+
+                switch (grid[i][j]) {
+                    case '/':
+                        g[y][x] = g[y + 1][x + 1] = 0;
+                        g[y][x + 1] = g[y + 1][x] = 1;
+                        break;
+
+                    case '\\':
+                        g[y][x] = g[y + 1][x + 1] = 2;
+                        g[y][x + 1] = g[y + 1][x] = 0;
+                        break;
+
+                    default:
+                        g[y][x] = g[y][x + 1] = g[y + 1][x] = g[y + 1][x + 1] = 0;
+                        break;
+                }
+            }
+        }
+
+        return g;
+    };
+
+    const isValid = (x: number) => 0 <= x && x < n;
+    const dfs = (i: number, j: number) => {
+        if (!isValid(i) || !isValid(j) || g[i][j]) return;
+
+        g[i][j] = -1;
+        const dirs = [-1, 0, 1, 0, -1];
+        const neighbours: number[] = [];
+
+        for (let d = 0; d < 4; d++) {
+            const [y, x] = [i + dirs[d], j + dirs[d + 1]];
+
+            if (isValid(y) && isValid(x)) {
+                dfs(y, x);
+                neighbours.push(g[y][x]);
+            } else {
+                neighbours.push(-1);
+            }
+        }
+
+        const [top, right, bottom, left] = neighbours;
+        if (top === 1 && right === 1) dfs(i - 1, j + 1);
+        if (bottom === 1 && left === 1) dfs(i + 1, j - 1);
+        if (top === 2 && left === 2) dfs(i - 1, j - 1);
+        if (bottom === 2 && right === 2) dfs(i + 1, j + 1);
+    };
+
+    const g = createGraph();
+    const n = g.length;
+    let res = 0;
+
+    for (let i = 0; i < n; i++) {
+        for (let j = 0; j < n; j++) {
+            if (g[i][j] === 0) {
+                dfs(i, j);
+                res++;
+            }
+        }
+    }
+
+    return res;
+}
+```
+
+<!-- tabs:end -->
+
+<!-- solution:end -->
+
 <!-- problem:end -->

solution/0900-0999/0959.Regions Cut By Slashes/Solution2.ts

@@ -0,0 +1,71 @@
+function regionsBySlashes(grid: string[]): number {
+    const createGraph = () => {
+        const n = grid.length;
+        const g = Array.from({ length: n * 2 }, () => Array(n * 2).fill(0));
+
+        for (let i = 0; i < n; i++) {
+            for (let j = 0; j < n; j++) {
+                const [y, x] = [i * 2, j * 2];
+
+                switch (grid[i][j]) {
+                    case '/':
+                        g[y][x] = g[y + 1][x + 1] = 0;
+                        g[y][x + 1] = g[y + 1][x] = 1;
+                        break;
+
+                    case '\\':
+                        g[y][x] = g[y + 1][x + 1] = 2;
+                        g[y][x + 1] = g[y + 1][x] = 0;
+                        break;
+
+                    default:
+                        g[y][x] = g[y][x + 1] = g[y + 1][x] = g[y + 1][x + 1] = 0;
+                        break;
+                }
+            }
+        }
+
+        return g;
+    };
+
+    const isValid = (x: number) => 0 <= x && x < n;
+    const dfs = (i: number, j: number) => {
+        if (!isValid(i) || !isValid(j) || g[i][j]) return;
+
+        g[i][j] = -1;
+        const dirs = [-1, 0, 1, 0, -1];
+        const neighbours: number[] = [];
+
+        for (let d = 0; d < 4; d++) {
+            const [y, x] = [i + dirs[d], j + dirs[d + 1]];
+
+            if (isValid(y) && isValid(x)) {
+                dfs(y, x);
+                neighbours.push(g[y][x]);
+            } else {
+                neighbours.push(-1);
+            }
+        }
+
+        const [top, right, bottom, left] = neighbours;
+        if (top === 1 && right === 1) dfs(i - 1, j + 1);
+        if (bottom === 1 && left === 1) dfs(i + 1, j - 1);
+        if (top === 2 && left === 2) dfs(i - 1, j - 1);
+        if (bottom === 2 && right === 2) dfs(i + 1, j + 1);
+    };
+
+    const g = createGraph();
+    const n = g.length;
+    let res = 0;
+
+    for (let i = 0; i < n; i++) {
+        for (let j = 0; j < n; j++) {
+            if (g[i][j] === 0) {
+                dfs(i, j);
+                res++;
+            }
+        }
+    }
+
+    return res;
+}