dsalgo 0.3.10

A package for Datastructures and Algorithms.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136

pub struct UnionFind(Vec<isize>);

impl UnionFind {
    pub fn new(size: usize) -> Self {
        Self(vec![-1; size])
    }

    pub fn size(&self) -> usize {
        self.0.len()
    }

    pub fn root(
        &mut self,
        u: usize,
    ) -> usize {
        if self.0[u] < 0 {
            return u;
        }

        let r = self.root(self.0[u] as usize);

        self.0[u] = r as isize;

        return r;
    }

    pub fn unite(
        &mut self,
        mut u: usize,
        mut v: usize,
    ) {
        u = self.root(u);

        v = self.root(v);

        if u == v {
            return;
        }

        if self.0[u] > self.0[v] {
            std::mem::swap(&mut u, &mut v);
            // (u, v) = (v, u);
        }

        self.0[u] += self.0[v];

        self.0[v] = u as isize;
    }

    pub fn size_of(
        &mut self,
        mut u: usize,
    ) -> usize {
        u = self.root(u);

        -self.0[u] as usize
    }

    pub fn same(
        &mut self,
        u: usize,
        v: usize,
    ) -> bool {
        self.root(u) == self.root(v)
    }

    pub fn labels(&mut self) -> Vec<usize> {
        let n = self.size();

        let mut labels = vec![n; n];

        let mut l = 0;

        for i in 0..n {
            let r = self.root(i);

            if labels[r] == n {
                labels[r] = l;

                l += 1;
            }

            labels[i] = labels[r];
        }

        labels
    }
}

#[cfg(test)]

mod tests {

    use super::*;

    #[test]

    fn test() {
        let mut uf = UnionFind::new(10);

        assert_eq!(uf.size_of(0), 1);

        uf.unite(3, 9);

        assert_eq!(uf.size_of(3), 2);
    }

    #[test]

    fn test_practice2_b() {
        let cases = vec![(
            4,
            vec![
                ((1, 0, 1), 0),
                ((0, 0, 1), 2),
                ((0, 2, 3), 2),
                ((1, 0, 1), 1),
                ((1, 1, 2), 0),
                ((0, 0, 2), 2),
                ((1, 1, 3), 1),
            ],
        )];

        for (n, q) in cases {
            let mut uf = UnionFind::new(n);

            for ((t, u, v), ans) in q {
                if t == 0 {
                    uf.unite(u, v);
                } else {
                    assert_eq!(if uf.same(u, v) { 1 } else { 0 }, ans);
                }
            }
        }
    }
}