hpdg 0.1.0

Rust-first data generator for competitive programming and OI workflows.
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
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291

//! Random vector and matrix helpers.
//!
//! This module is handy for generators that need points, tuples, matrices, or generic
//! multi-dimensional integer data.
//!
//! # Example
//!
//! ```rust
//! use hpdg::vector::{IntRange, Vector};
//!
//! let rows = Vector::random_matrix(2, 3, IntRange::MinMax(1, 9));
//! assert_eq!(rows.len(), 2);
//! assert!(rows.iter().all(|row| row.len() == 3));
//! ```

use rand::Rng;
use std::collections::HashSet;

/// Modes for random vector generation.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum VectorRandomMode {
    Unique,
    Repeatable,
    Float,
}

/// Integer range specification for each dimension.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum IntRange {
    /// Inclusive range `[0, max]`.
    Max(i64),
    /// Inclusive range `[min, max]`.
    MinMax(i64, i64),
}

impl From<i64> for IntRange {
    fn from(value: i64) -> Self {
        IntRange::Max(value)
    }
}

impl From<(i64, i64)> for IntRange {
    fn from(value: (i64, i64)) -> Self {
        IntRange::MinMax(value.0, value.1)
    }
}

/// Collection type returned by integer-vector generators.
pub type IntVector = Vec<Vec<i64>>;
/// Collection type returned by floating-point vector generators.
pub type FloatVector = Vec<Vec<f64>>;

/// Floating-point range specification for each dimension.
#[derive(Debug, Clone, Copy, PartialEq)]
pub enum FloatRange {
    /// Inclusive range `[0.0, max]`.
    Max(f64),
    /// Inclusive range `[min, max]`.
    MinMax(f64, f64),
}

impl From<f64> for FloatRange {
    fn from(value: f64) -> Self {
        FloatRange::Max(value)
    }
}

impl From<(f64, f64)> for FloatRange {
    fn from(value: (f64, f64)) -> Self {
        FloatRange::MinMax(value.0, value.1)
    }
}

/// Vector utilities (random generators, helpers).
pub struct Vector;

fn normalize_int_ranges(position_range: &[IntRange]) -> Vec<IntRange> {
    if position_range.is_empty() {
        vec![IntRange::Max(10)]
    } else {
        position_range.to_vec()
    }
}

fn parse_int_ranges(ranges: &[IntRange]) -> (Vec<i64>, Vec<i64>) {
    let mut offsets: Vec<i64> = Vec::with_capacity(ranges.len());
    let mut lengths: Vec<i64> = Vec::with_capacity(ranges.len());
    for range in ranges {
        match *range {
            IntRange::Max(max) => {
                offsets.push(0);
                lengths.push(max);
            }
            IntRange::MinMax(min, max) => {
                assert!(max >= min, "upper-bound should be larger than lower-bound");
                offsets.push(min);
                lengths.push(max - min);
            }
        }
    }
    (offsets, lengths)
}

fn normalize_float_ranges(position_range: &[FloatRange]) -> Vec<FloatRange> {
    if position_range.is_empty() {
        vec![FloatRange::Max(10.0)]
    } else {
        position_range.to_vec()
    }
}

fn parse_float_ranges(ranges: &[FloatRange]) -> (Vec<f64>, Vec<f64>) {
    let mut offsets: Vec<f64> = Vec::with_capacity(ranges.len());
    let mut lengths: Vec<f64> = Vec::with_capacity(ranges.len());
    for range in ranges {
        match *range {
            FloatRange::Max(max) => {
                offsets.push(0.0);
                lengths.push(max);
            }
            FloatRange::MinMax(min, max) => {
                assert!(max >= min, "upper-bound should be larger than lower-bound");
                offsets.push(min);
                lengths.push(max - min);
            }
        }
    }
    (offsets, lengths)
}

fn vector_space(lengths: &[i64]) -> u128 {
    lengths
        .iter()
        .fold(1u128, |acc, &len| acc * (len as u128 + 1))
}

fn get_vector_from_index(lengths: &[i64], mut hashcode: u128) -> Vec<i64> {
    let mut tmp: Vec<i64> = Vec::with_capacity(lengths.len());
    for &len in lengths {
        let base = len as u128 + 1;
        tmp.push((hashcode % base) as i64);
        hashcode /= base;
    }
    tmp
}

impl Vector {
    /// Generate random integer vectors (duplicates allowed).
    pub fn random_int(num: usize, position_range: &[IntRange]) -> IntVector {
        let ranges = normalize_int_ranges(position_range);
        let (offsets, lengths) = parse_int_ranges(&ranges);

        let mut rng = rand::rng();
        let mut result: IntVector = Vec::with_capacity(num);
        for _ in 0..num {
            let mut vec = Vec::with_capacity(ranges.len());
            for (&offset, &length) in offsets.iter().zip(lengths.iter()) {
                let val = rng.random_range(offset..=offset + length);
                vec.push(val);
            }
            result.push(vec);
        }
        result
    }

    /// Generate random integer vectors without duplicates.
    pub fn random_unique_vector(num: usize, position_range: &[IntRange]) -> IntVector {
        let ranges = normalize_int_ranges(position_range);
        let (offsets, lengths) = parse_int_ranges(&ranges);
        let space = vector_space(&lengths);
        assert!(num as u128 <= space, "not enough unique vectors in range");

        let mut rng = rand::rng();
        let mut used: HashSet<u128> = HashSet::with_capacity(num * 2 + 1);
        let mut result: IntVector = Vec::with_capacity(num);
        while result.len() < num {
            let rand_idx = rng.random_range(0..space);
            if used.insert(rand_idx) {
                let mut vec = get_vector_from_index(&lengths, rand_idx);
                for (v, offset) in vec.iter_mut().zip(offsets.iter()) {
                    *v += *offset;
                }
                result.push(vec);
            }
        }
        result
    }

    /// Generate random integer vectors with duplicates allowed (alias).
    pub fn random_repeatable_vector(num: usize, position_range: &[IntRange]) -> IntVector {
        Self::random_int(num, position_range)
    }

    /// Generate random floating-point vectors.
    pub fn random_float_vector(num: usize, position_range: &[FloatRange]) -> FloatVector {
        let ranges = normalize_float_ranges(position_range);
        let (offsets, lengths) = parse_float_ranges(&ranges);

        let mut rng = rand::rng();
        let mut result: FloatVector = Vec::with_capacity(num);
        for _ in 0..num {
            let mut vec = Vec::with_capacity(ranges.len());
            for (&offset, &length) in offsets.iter().zip(lengths.iter()) {
                let val = rng.random_range(offset..=offset + length);
                vec.push(val);
            }
            result.push(vec);
        }
        result
    }

    /// Convert an index into a vector based on the provided integer ranges.
    pub fn get_vector(position_range: &[IntRange], hashcode: u128) -> Vec<i64> {
        let ranges = normalize_int_ranges(position_range);
        let (offsets, lengths) = parse_int_ranges(&ranges);
        let mut vec = get_vector_from_index(&lengths, hashcode);
        for (v, offset) in vec.iter_mut().zip(offsets.iter()) {
            *v += *offset;
        }
        vec
    }

    /// Generate an integer matrix with the same range for each column.
    pub fn random_matrix(rows: usize, cols: usize, range: IntRange) -> IntVector {
        let ranges = vec![range; cols];
        Self::random_int(rows, &ranges)
    }

    /// Format a vector with a custom separator.
    pub fn format_vector<T: std::fmt::Display>(vec: &[T], sep: &str) -> String {
        vec.iter()
            .map(|v| v.to_string())
            .collect::<Vec<_>>()
            .join(sep)
    }

    /// Format a matrix using column and row separators.
    pub fn format_matrix<T: std::fmt::Display>(
        matrix: &[Vec<T>],
        sep: &str,
        row_sep: &str,
    ) -> String {
        matrix
            .iter()
            .map(|row| Self::format_vector(row, sep))
            .collect::<Vec<_>>()
            .join(row_sep)
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_get_vector() {
        let ranges = [IntRange::Max(2), IntRange::MinMax(3, 4)];
        assert_eq!(Vector::get_vector(&ranges, 0), vec![0, 3]);
        assert_eq!(Vector::get_vector(&ranges, 1), vec![1, 3]);
    }

    #[test]
    fn test_random_int_bounds() {
        let ranges = [IntRange::Max(1)];
        let vectors = Vector::random_int(3, &ranges);
        assert_eq!(vectors.len(), 3);
        for v in vectors {
            assert_eq!(v.len(), 1);
            assert!(v[0] >= 0 && v[0] <= 1);
        }
    }

    #[test]
    fn test_random_unique_vectors() {
        let ranges = [IntRange::Max(1), IntRange::Max(1)];
        let vectors = Vector::random_unique_vector(4, &ranges);
        let mut set = std::collections::HashSet::new();
        for v in vectors {
            set.insert(v);
        }
        assert_eq!(set.len(), 4);
    }

    #[test]
    fn test_formatting_helpers() {
        let v = vec![1, 2, 3];
        assert_eq!(Vector::format_vector(&v, ","), "1,2,3");
        let m = vec![vec![1, 2], vec![3, 4]];
        assert_eq!(Vector::format_matrix(&m, " ", "\n"), "1 2\n3 4");
    }
}