Rust Gym Leetcode 1725 Number Of Rectangles That Can Form The Largest Square Rust Solution

1725. Number Of Rectangles That Can Form The Largest Square

You are given an array rectangles where rectangles[i] = [l_i, w_i] represents the i^th rectangle of length l_i and width w_i.

You can cut the i^th rectangle to form a square with a side length of k if both k <= l_i and k <= w_i. For example, if you have a rectangle [4,6], you can cut it to get a square with a side length of at most 4.

Let maxLen be the side length of the largest square you can obtain from any of the given rectangles.

Return the number of rectangles that can make a square with a side length of maxLen.

Example 1:

Input: rectangles = [[5,8],[3,9],[5,12],[16,5]]
Output: 3
Explanation: The largest squares you can get from each rectangle are of lengths [5,3,5,5].
The largest possible square is of length 5, and you can get it out of 3 rectangles.

Example 2:

Input: rectangles = [[2,3],[3,7],[4,3],[3,7]]
Output: 3

Constraints:

1 <= rectangles.length <= 1000
rectangles[i].length == 2
1 <= l_i, w_i <= 10⁹
l_i != w_i

1725. Number Of Rectangles That Can Form The Largest Square

struct Solution;

use std::collections::HashMap;

impl Solution {
    fn count_good_rectangles(rectangles: Vec<Vec<i32>>) -> i32 {
        let mut count: HashMap<i32, usize> = HashMap::new();
        let mut max = 0;
        for rect in rectangles {
            let min = rect[0].min(rect[1]);
            *count.entry(min).or_default() += 1;
            max = max.max(min);
        }
        count[&max] as i32
    }
}

#[test]
fn test() {
    let rectangles = vec_vec_i32![[5, 8], [3, 9], [5, 12], [16, 5]];
    let res = 3;
    assert_eq!(Solution::count_good_rectangles(rectangles), res);
    let rectangles = vec_vec_i32![[2, 3], [3, 7], [4, 3], [3, 7]];
    let res = 3;
    assert_eq!(Solution::count_good_rectangles(rectangles), res);
}