function printMatrix(matrix: number[][]): void {
matrix.forEach((row: number[]) => console.log(row.join(" ")));
}
/**
* Rotates a square matrix 90 degrees to the left (counterclockwise).
* @param matrix - The square matrix to rotate.
*/
function rotateMatrix90DegreesLeft(matrix: number[][]): void {
const len: number = matrix.length;
// Validate input: Ensure it's a square matrix
if (
!Array.isArray(matrix) ||
!matrix.every((row: number[]) => Array.isArray(row) && row.length === len)
) {
throw new Error("Input must be a square matrix.");
}
// Perform the rotation in-place
for (let layer = 0; layer < Math.floor(len / 2); layer++) {
const first = layer;
const last = len - 1 - layer;
for (let i = first; i < last; i++) {
const offset = i - first;
// Save the top element
const top: number = matrix[first][i];
// Move right to top
matrix[first][i] = matrix[i][last];
// Move bottom to right
matrix[i][last] = matrix[last][last - offset];
// Move left to bottom
matrix[last][last - offset] = matrix[last - offset][first];
// Move top to left
matrix[last - offset][first] = top;
}
}
}
const matrix: number[][] = [
[1, 2, 3],
[4, 5, 6],
[7, 8, 9]
];
rotateMatrix90DegreesLeft(matrix);
console.log("Matrix After 90° Left Rotation:");
printMatrix(matrix);
/*
run:
"Matrix After 90° Left Rotation:"
"3 6 9"
"2 5 8"
"1 4 7"
*/
