rustgym/leetcode/
_785_is_graph_bipartite.rs

1struct Solution;
2use std::collections::HashSet;
3
4struct Graph {
5    edges: Vec<HashSet<usize>>,
6    nodes: Vec<i32>,
7    n: usize,
8}
9
10impl Graph {
11    fn new(n: usize) -> Self {
12        let edges: Vec<HashSet<usize>> = vec![HashSet::new(); n];
13        let nodes: Vec<i32> = vec![0; n];
14        Graph { edges, nodes, n }
15    }
16
17    fn insert_edge(&mut self, u: usize, v: usize) {
18        self.edges[u].insert(v);
19    }
20
21    fn dfs(&mut self, u: usize, color: i32) -> bool {
22        if self.nodes[u] == 0 {
23            self.nodes[u] = color;
24            for v in self.edges[u].clone() {
25                if !self.dfs(v, -color) {
26                    return false;
27                }
28            }
29        } else {
30            return self.nodes[u] == color;
31        }
32        true
33    }
34}
35
36impl Solution {
37    fn is_bipartite(graph: Vec<Vec<i32>>) -> bool {
38        let n = graph.len();
39        let mut g = Graph::new(n);
40        for u in 0..n {
41            for &v in &graph[u] {
42                g.insert_edge(u, v as usize);
43            }
44        }
45        for u in 0..n {
46            if g.nodes[u] == 0 && !g.dfs(u, 1) {
47                return false;
48            }
49        }
50        true
51    }
52}
53
54#[test]
55fn test() {
56    let graph = vec![vec![1, 3], vec![0, 2], vec![1, 3], vec![0, 2]];
57    let res = true;
58    assert_eq!(Solution::is_bipartite(graph), res);
59    let graph = vec![vec![1, 2, 3], vec![0, 2], vec![0, 1, 3], vec![0, 2]];
60    let res = false;
61    assert_eq!(Solution::is_bipartite(graph), res);
62    let graph = vec![
63        vec![],
64        vec![2, 4, 6],
65        vec![1, 4, 8, 9],
66        vec![7, 8],
67        vec![1, 2, 8, 9],
68        vec![6, 9],
69        vec![1, 5, 7, 8, 9],
70        vec![3, 6, 9],
71        vec![2, 3, 4, 6, 9],
72        vec![2, 4, 5, 6, 7, 8],
73    ];
74    let res = false;
75    assert_eq!(Solution::is_bipartite(graph), res);
76}
rustgym/leetcode/_785_is_graph_bipartite.rs

rustgym/leetcode/
_785_is_graph_bipartite.rs
