Wrote program for Day 52

README.md

@@ -98,7 +98,7 @@ We encourage you to share your progress and ask questions in the Discussions sec
 | Day #49       | [Swimming Pool](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-07/Day-49_Swimming-Pool)                         | :white_check_mark:      |
 | Day #50       | [Tic Tac Toe](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-08/Day-50_Tic-Tac-Toe)                           | :white_check_mark:      |
 | Day #51       | [Asteroid Collision](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-08/Day-51_Asteroid-Collision)                    | :white_check_mark:      |
-| Day #52       | [Switch On The Gravity](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-08/Day-52_Switch-On-The-Gravity)                 | :white_large_square:      |
+| Day #52       | [Switch On The Gravity](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-08/Day-52_Switch-On-The-Gravity)                 | :white_check_mark:      |
 | Day #53       | [Javelin Parabolic Throw](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-08/Day-53_Javelin-Parabolic-Throw)               | :white_large_square:      |
 | Day #54       | [RGB To Hex Color Convertor](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-08/Day-54_RGB-To-Hex-Color-Converter)            | :white_large_square:      |
 | Day #55       | [Filter Repeating Character Strings](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-08/Day-55_Filter_Repeating-Character-Strings)    | :white_large_square:      |

Week-08/Day-52_Switch-On-The-Gravity/day52/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "day52"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

Week-08/Day-52_Switch-On-The-Gravity/day52/src/lib.rs

@@ -0,0 +1,22 @@
+pub fn switch_gravity_on(matrix: &Vec<Vec<char>>) -> Option<Vec<Vec<char>>> {
+    let mut column = vec![0usize; matrix.first()?.len()];
+    for row in matrix {
+        for (i, cell) in row.iter().enumerate() {
+            if *cell == '#' {
+                *column.get_mut(i)? += 1;
+            }
+        }
+    }
+
+    let mut final_matrix = matrix.clone();
+    for (i, row) in final_matrix.iter_mut().enumerate() {
+        for (j, cell) in row.iter_mut().enumerate() {
+            *cell = if i >= matrix.len() - column.get(j)? {
+                '#'
+            } else {
+                '-'
+            };
+        }
+    }
+    Some(final_matrix)
+}

Week-08/Day-52_Switch-On-The-Gravity/day52/src/main.rs

@@ -0,0 +1,45 @@
+use std::process::exit;
+
+use day52::switch_gravity_on;
+
+fn read_matrix() -> Result<Vec<Vec<char>>, String> {
+    let mut matrix: Vec<Vec<char>> = Vec::new();
+    loop {
+        let mut row = String::new();
+        std::io::stdin().read_line(&mut row).unwrap();
+        if row.trim().chars().any(|c| c != '#' && c != '-') {
+            return Err("Invalid character in input".to_owned());
+        }
+        if row.trim().is_empty() {
+            break;
+        }
+        matrix.push(row.trim().chars().collect());
+    }
+    if matrix
+        .iter()
+        .any(|row| row.len() != matrix.first().unwrap().len())
+    {
+        return Err("All rows must have the same length".to_owned());
+    }
+    Ok(matrix)
+}
+
+fn main() {
+    println!("Enter the matrix line by line without spaces (empty line to finish)");
+    println!("Use # for blocks and - for empty spaces");
+    let matrix = match read_matrix() {
+        Ok(matrix) => matrix,
+        Err(e) => {
+            eprintln!("Error: {}", e);
+            exit(1);
+        }
+    };
+    let result = match switch_gravity_on(&matrix) {
+        Some(matrix) => matrix,
+        None => {
+            eprintln!("Error: Invalid input");
+            exit(1);
+        }
+    };
+    println!("{:?}", result);
+}

Week-08/Day-52_Switch-On-The-Gravity/day52/tests/examples.rs

@@ -0,0 +1,53 @@
+#[cfg(test)]
+mod examples {
+    use day52::switch_gravity_on;
+
+    #[test]
+    fn example1() {
+        let matrix = vec![
+            vec!['-', '#', '#', '-'],
+            vec!['-', '-', '-', '-'],
+            vec!['-', '-', '-', '-'],
+            vec!['-', '-', '-', '-'],
+        ];
+        let expected = vec![
+            vec!['-', '-', '-', '-'],
+            vec!['-', '-', '-', '-'],
+            vec!['-', '-', '-', '-'],
+            vec!['-', '#', '#', '-'],
+        ];
+        assert_eq!(switch_gravity_on(&matrix), Some(expected));
+    }
+
+    #[test]
+    fn example2() {
+        let matrix = vec![
+            vec!['-', '#', '#', '-'],
+            vec!['-', '-', '#', '-'],
+            vec!['-', '-', '-', '-'],
+        ];
+        let expected = vec![
+            vec!['-', '-', '-', '-'],
+            vec!['-', '-', '#', '-'],
+            vec!['-', '#', '#', '-'],
+        ];
+        assert_eq!(switch_gravity_on(&matrix), Some(expected));
+    }
+
+    #[test]
+    fn example3() {
+        let matrix = vec![
+            vec!['-', '#', '#', '#', '#', '-'],
+            vec!['#', '-', '-', '#', '#', '-'],
+            vec!['-', '#', '-', '-', '-', '-'],
+            vec!['-', '-', '-', '-', '-', '-'],
+        ];
+        let expected = vec![
+            vec!['-', '-', '-', '-', '-', '-'],
+            vec!['-', '-', '-', '-', '-', '-'],
+            vec!['-', '#', '-', '#', '#', '-'],
+            vec!['#', '#', '#', '#', '#', '-'],
+        ];
+        assert_eq!(switch_gravity_on(&matrix), Some(expected));
+    }
+}