All files / algorithms matrices.ts

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41x
 
 
 
 
1x
1x
 
1x
4x
16x
 
 
 
1x
 
 
1x
2x
2x
 
2x
 
2x
 
 
1x
1x
1x
 
1x
 
1x
4x
4x
 
 
1x
 
 
1x
1x
1x
 
1x
 
1x
4x
4x
 
 
1x
 
 
2x
1x
 
1x
1x
 
 
1x
4x
 
 
 
1x
2x
 
 
1x
 
 
/**
 * The assumptions is that the matrices are N x M (either square or rectangular)
 * The matrices cannot have rows with different sizes.
 */
 
export function sum(matrix: number[][]): number {
  let sum = 0;
 
  for (let i = 0; i < matrix.length; i += 1) {
    for (let j = 0; j < matrix[i].length; j += 1) {
      sum += matrix[i][j];
    }
  }
 
  return sum;
}
 
function getShortestLength(matrix: number[][]): number {
  const rows = matrix.length;
  const columns = matrix[0].length;
 
  Iif (rows < columns) return rows;
 
  return columns;
}
 
export function sumDiagonal(matrix: number[][]): number {
  let sum = 0;
  let index = 0;
 
  const shortestLength = getShortestLength(matrix);
 
  while (index < shortestLength) {
    sum += matrix[index][index];
    index += 1;
  }
 
  return sum;
}
 
export function sumAntiDiagonal(matrix: number[][]): number {
  let sum = 0;
  let index = 0;
 
  const shortestLength = getShortestLength(matrix);
 
  while (index < shortestLength) {
    sum += matrix[index][matrix.length - 1 - index];
    index += 1;
  }
 
  return sum;
}
 
export function sumFrame(matrix: number[][]): number {
  let sum = 0;
 
  const numberOfRows = matrix.length;
  const numberOfColumns = matrix[0].length; // assuming every row has the same size
 
  // scann horizontally: top + bottom
  for (let index = 0; index < numberOfColumns; index += 1) {
    sum += matrix[0][index] + matrix[numberOfRows - 1][index];
  }
 
  // scan vertically: left + right
  for (let index = 1; index < numberOfRows - 1; index += 1) {
    sum += matrix[index][0] + matrix[index][numberOfColumns - 1];
  }
 
  return sum;
}