https://leetcode.cn/problems/add-edges-to-make-degrees-of-all-nodes-even/

Author: masx200

README.md

@@ -45,6 +45,8 @@ Step 2. Add the dependency
 
 <summary>展开查看</summary>
 
+https://leetcode.cn/problems/add-edges-to-make-degrees-of-all-nodes-even/
+
 https://leetcode.cn/problems/smallest-value-after-replacing-with-sum-of-prime-factors
 
 https://leetcode.cn/problems/count-pairs-of-similar-strings

add-edges-to-make-degrees-of-all-nodes-even/index.ts

@@ -0,0 +1,48 @@
+function isPossible(n: number, edges: number[][]): boolean {
+    const s = new Set<string>();
+
+    const deg = new Map<number, number>();
+
+    for (const [x, y] of edges) {
+        s.add(JSON.stringify([x, y]));
+        s.add(JSON.stringify([y, x]));
+
+        deg.set(x, (deg.get(x) ?? 0) + 1);
+        deg.set(y, (deg.get(y) ?? 0) + 1);
+    }
+
+    const odd = [...deg].filter(([_, d]) => d % 2 > 0).map((a) => a[0]);
+
+    const m = odd.length;
+
+    if (m === 0) return true;
+
+    if (m === 2) {
+        const x = odd[0];
+        const y = odd[1];
+
+        if (!s.has(JSON.stringify([x, y]))) {
+            return true;
+        }
+        for (let i = 1; i <= n; i++) {
+            if (
+                i != x &&
+                i != y &&
+                !s.has(JSON.stringify([i, x])) &&
+                !s.has(JSON.stringify([i, y]))
+            ) {
+                return true;
+            }
+        }
+        return false;
+    }
+    if (m == 4) {
+        const [a, b, c, d] = odd;
+        return !s.has(JSON.stringify([a, b])) &&
+                !s.has(JSON.stringify([c, d])) ||
+            !s.has(JSON.stringify([a, c])) && !s.has(JSON.stringify([b, d])) ||
+            !s.has(JSON.stringify([a, d])) && !s.has(JSON.stringify([b, c]));
+    }
+    return false;
+}
+export default isPossible;