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feat: add rust solution to lc problem: No.0085 (#1528)
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‎solution/0000-0099/0085.Maximal Rectangle/README.md

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Original file line numberDiff line numberDiff line change
@@ -194,6 +194,86 @@ public:
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};
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```
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### **Rust**
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```rust
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impl Solution {
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#[allow(dead_code)]
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pub fn maximal_rectangle(matrix: Vec<Vec<char>>) -> i32 {
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let n = matrix[0].len();
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let mut heights = vec![0; n];
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let mut ret = -1;
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for row in &matrix {
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Self::array_builder(row, &mut heights);
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ret = std::cmp::max(ret, Self::largest_rectangle_area(heights.clone()));
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}
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ret
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}
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/// Helper function, build the heights array according to the input
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#[allow(dead_code)]
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fn array_builder(input: &Vec<char>, heights: &mut Vec<i32>) {
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for (i, &c) in input.iter().enumerate() {
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heights[i] += match c {
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'1' => 1,
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'0' => {
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heights[i] = 0;
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0
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}
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_ => panic!("This is impossible"),
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};
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}
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}
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/// Helper function, see: https://leetcode.com/problems/largest-rectangle-in-histogram/ for details
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#[allow(dead_code)]
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fn largest_rectangle_area(heights: Vec<i32>) -> i32 {
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let n = heights.len();
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let mut left = vec![-1; n];
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let mut right = vec![-1; n];
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let mut stack: Vec<(usize, i32)> = Vec::new();
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let mut ret = -1;
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// Build left vector
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for (i, h) in heights.iter().enumerate() {
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while !stack.is_empty() && stack.last().unwrap().1 >= *h {
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stack.pop();
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}
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if stack.is_empty() {
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left[i] = -1;
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} else {
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left[i] = stack.last().unwrap().0 as i32;
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}
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stack.push((i, *h));
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}
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stack.clear();
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// Build right vector
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for (i, h) in heights.iter().enumerate().rev() {
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while !stack.is_empty() && stack.last().unwrap().1 >= *h {
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stack.pop();
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}
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if stack.is_empty() {
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right[i] = n as i32;
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} else {
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right[i] = stack.last().unwrap().0 as i32;
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}
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stack.push((i, *h));
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}
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// Calculate the max area
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for (i, h) in heights.iter().enumerate() {
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ret = std::cmp::max(ret, (right[i] - left[i] - 1) * *h);
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}
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ret
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}
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}
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```
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### **Go**
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```go

‎solution/0000-0099/0085.Maximal Rectangle/README_EN.md

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Original file line numberDiff line numberDiff line change
@@ -164,6 +164,86 @@ public:
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};
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```
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### **Rust**
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```rust
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impl Solution {
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#[allow(dead_code)]
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pub fn maximal_rectangle(matrix: Vec<Vec<char>>) -> i32 {
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let n = matrix[0].len();
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let mut heights = vec![0; n];
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let mut ret = -1;
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for row in &matrix {
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Self::array_builder(row, &mut heights);
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ret = std::cmp::max(ret, Self::largest_rectangle_area(heights.clone()));
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}
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ret
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}
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/// Helper function, build the heights array according to the input
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#[allow(dead_code)]
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fn array_builder(input: &Vec<char>, heights: &mut Vec<i32>) {
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for (i, &c) in input.iter().enumerate() {
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heights[i] += match c {
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'1' => 1,
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'0' => {
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heights[i] = 0;
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0
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}
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_ => panic!("This is impossible"),
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};
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}
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}
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/// Helper function, see: https://leetcode.com/problems/largest-rectangle-in-histogram/ for details
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#[allow(dead_code)]
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fn largest_rectangle_area(heights: Vec<i32>) -> i32 {
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let n = heights.len();
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let mut left = vec![-1; n];
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let mut right = vec![-1; n];
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let mut stack: Vec<(usize, i32)> = Vec::new();
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let mut ret = -1;
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// Build left vector
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for (i, h) in heights.iter().enumerate() {
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while !stack.is_empty() && stack.last().unwrap().1 >= *h {
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stack.pop();
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}
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if stack.is_empty() {
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left[i] = -1;
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} else {
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left[i] = stack.last().unwrap().0 as i32;
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}
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stack.push((i, *h));
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}
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stack.clear();
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// Build right vector
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for (i, h) in heights.iter().enumerate().rev() {
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while !stack.is_empty() && stack.last().unwrap().1 >= *h {
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stack.pop();
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}
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if stack.is_empty() {
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right[i] = n as i32;
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} else {
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right[i] = stack.last().unwrap().0 as i32;
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}
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stack.push((i, *h));
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}
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// Calculate the max area
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for (i, h) in heights.iter().enumerate() {
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ret = std::cmp::max(ret, (right[i] - left[i] - 1) * *h);
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}
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ret
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}
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}
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```
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### **Go**
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```go

‎solution/0000-0099/0085.Maximal Rectangle/Solution.rs

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impl Solution {
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#[allow(dead_code)]
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pub fn maximal_rectangle(matrix: Vec<Vec<char>>) -> i32 {
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let n = matrix[0].len();
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let mut heights = vec![0; n];
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let mut ret = -1;
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for row in &matrix {
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Self::array_builder(row, &mut heights);
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ret = std::cmp::max(ret, Self::largest_rectangle_area(heights.clone()));
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}
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ret
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}
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/// Helper function, build the heights array according to the input
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#[allow(dead_code)]
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fn array_builder(input: &Vec<char>, heights: &mut Vec<i32>) {
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for (i, &c) in input.iter().enumerate() {
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heights[i] += match c {
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'1' => 1,
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'0' => {
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heights[i] = 0;
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0
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}
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_ => panic!("This is impossible"),
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};
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}
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}
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/// Helper function, see: https://leetcode.com/problems/largest-rectangle-in-histogram/ for details
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#[allow(dead_code)]
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fn largest_rectangle_area(heights: Vec<i32>) -> i32 {
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let n = heights.len();
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let mut left = vec![-1; n];
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let mut right = vec![-1; n];
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let mut stack: Vec<(usize, i32)> = Vec::new();
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let mut ret = -1;
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// Build left vector
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for (i, h) in heights.iter().enumerate() {
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while !stack.is_empty() && stack.last().unwrap().1 >= *h {
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stack.pop();
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}
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if stack.is_empty() {
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left[i] = -1;
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} else {
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left[i] = stack.last().unwrap().0 as i32;
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}
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stack.push((i, *h));
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}
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stack.clear();
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// Build right vector
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for (i, h) in heights.iter().enumerate().rev() {
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while !stack.is_empty() && stack.last().unwrap().1 >= *h {
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stack.pop();
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}
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if stack.is_empty() {
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right[i] = n as i32;
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} else {
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right[i] = stack.last().unwrap().0 as i32;
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}
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stack.push((i, *h));
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}
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// Calculate the max area
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for (i, h) in heights.iter().enumerate() {
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ret = std::cmp::max(ret, (right[i] - left[i] - 1) * *h);
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}
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ret
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}
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}

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