Merge pull request #8 from jakubjirous/feature/diagonal-difference

5) Diagonal Difference

Author: Jakub Jirous

README.md

@@ -26,3 +26,4 @@ Developers compete by writing programs according to provided specifications.
 2. [Mini-Max Sum](/src/challenges/02-mini-max-sum/INDEX.md)
 3. [Time Conversion](/src/challenges/03-time-conversion/INDEX.md)
 4. [Lonely Integer](/src/challenges/04-lonely-integer/INDEX.md)
+5. [Diagonal Difference](/src/challenges/05-diagonal-difference/INDEX.md)

src/challenges/01-plus-minus/test/plus-minus.test.ts

@@ -52,7 +52,7 @@ describe("Plus Minus", () => {
  ];
 
  test.each(cases)(
- "for given array of integers %p output should be %p",
+ "for given array of integers %j output should be %s",
  (firstArg, expectedResult) => {
  const result = plusMinus(firstArg);
  expect(result.trim()).toEqual(expectedResult.trim());

src/challenges/02-mini-max-sum/test/mini-max-sum.test.ts

@@ -47,7 +47,7 @@ describe("Mini-Max Sum", () => {
  ];
 
  test.each(cases)(
- "for given array of integers %p output should be %p",
+ "for given array of integers %j output should be %j",
  (firstArg, expectedResult) => {
  const result = miniMaxSum(firstArg);
  expect(result).toEqual(expectedResult);

src/challenges/03-time-conversion/test/time-conversion.test.ts

@@ -17,7 +17,7 @@ describe("Time Conversion", () => {
  ];
 
  test.each(cases)(
- "for given time %p output should be %p",
+ "for given time %s output should be %s",
  (firstArg, expectedResult) => {
  const result = timeConversion(firstArg);
  expect(result).toEqual(expectedResult);

src/challenges/04-lonely-integer/test/lonely-integer.test.ts

@@ -8,14 +8,44 @@ describe("Lonely Integer", () => {
  [[1, 1, 2], 2],
  [[0, 0, 1, 2, 1], 2],
  [[4, 9, 95, 93, 57, 4, 57, 93, 9], 95],
- [[34, 95, 34, 64, 45, 95, 16, 80, 80, 75, 3, 25, 75, 25, 31, 3, 64, 16, 31], 45],
- [[15, 60, 74, 1, 94, 93, 28, 48, 70, 98, 45, 94, 42, 45, 48, 1, 72, 9, 24, 93, 41, 70, 60, 28, 11, 20, 72, 35, 11, 98, 31, 74, 31, 41, 9, 42, 20, 35, 24], 15],
- [[18, 49, 15, 30, 56, 20, 49, 67, 82, 69, 84, 63, 93, 87, 66, 17, 38, 32, 17, 32, 94, 66, 67, 63, 48, 64, 84, 82, 87, 18, 79, 64, 79, 15, 71, 94, 59, 5, 22, 59, 4, 98, 81, 4, 98, 73, 69, 88, 30, 81, 48, 56, 71, 20, 93, 22, 73, 5, 88], 38],
- [[59, 88, 14, 8, 85, 1, 94, 74, 57, 96, 39, 2, 47, 43, 35, 17, 53, 52, 92, 31, 99, 48, 94, 30, 92, 60, 32, 45, 88, 13, 39, 50, 22, 65, 89, 46, 65, 76, 57, 67, 99, 35, 76, 46, 85, 82, 45, 62, 53, 80, 74, 22, 31, 52, 82, 13, 41, 96, 2, 1, 80, 62, 4, 20, 50, 89, 59, 67, 60, 8, 41, 14, 47, 48, 17, 4, 43, 30, 32], 20],
+ [
+ [
+ 34, 95, 34, 64, 45, 95, 16, 80, 80, 75, 3, 25, 75, 25, 31, 3, 64, 16,
+ 31,
+ ],
+ 45,
+ ],
+ [
+ [
+ 15, 60, 74, 1, 94, 93, 28, 48, 70, 98, 45, 94, 42, 45, 48, 1, 72, 9, 24,
+ 93, 41, 70, 60, 28, 11, 20, 72, 35, 11, 98, 31, 74, 31, 41, 9, 42, 20,
+ 35, 24,
+ ],
+ 15,
+ ],
+ [
+ [
+ 18, 49, 15, 30, 56, 20, 49, 67, 82, 69, 84, 63, 93, 87, 66, 17, 38, 32,
+ 17, 32, 94, 66, 67, 63, 48, 64, 84, 82, 87, 18, 79, 64, 79, 15, 71, 94,
+ 59, 5, 22, 59, 4, 98, 81, 4, 98, 73, 69, 88, 30, 81, 48, 56, 71, 20, 93,
+ 22, 73, 5, 88,
+ ],
+ 38,
+ ],
+ [
+ [
+ 59, 88, 14, 8, 85, 1, 94, 74, 57, 96, 39, 2, 47, 43, 35, 17, 53, 52, 92,
+ 31, 99, 48, 94, 30, 92, 60, 32, 45, 88, 13, 39, 50, 22, 65, 89, 46, 65,
+ 76, 57, 67, 99, 35, 76, 46, 85, 82, 45, 62, 53, 80, 74, 22, 31, 52, 82,
+ 13, 41, 96, 2, 1, 80, 62, 4, 20, 50, 89, 59, 67, 60, 8, 41, 14, 47, 48,
+ 17, 4, 43, 30, 32,
+ ],
+ 20,
+ ],
  ];
 
  test.each(cases)(
- "for given array of integers %p output should be %p",
+ "for given array of integers %j output should be %d",
  (firstArg, expectedResult) => {
  const result = lonelyInteger(firstArg);
  expect(result).toEqual(expectedResult);

src/challenges/05-diagonal-difference/INDEX.md

@@ -0,0 +1,64 @@
+# Diagonal Difference
+
+Given a square matrix, calculate the absolute difference between the sums of its diagonals.
+
+---
+
+### Example: 
+- For example, the square matrix `matrix` is shown below:
+
+```
+1 2 3
+4 5 6
+9 8 9 
+```
+- The left-to-right diagonal = `1 + 5 + 9 = 15`
+- The right to left diagonal = `3 + 5 + 9 = 17`
+- Their absolute difference is `|15 - 17| = 2`
+
+### Function Description:
+
+- Complete the `diagonalDifference` function in the editor below.
+- `diagonalDifference` diagonalDifference takes the following parameter:
+ - `int matrix[n][m]`: an array of integers
+
+### Returns:
+
+- `int`: the absolute diagonal difference
+
+### Input Format:
+
+- The first line contains a single integer, `n`, the number of rows and columns in the square matrix `matrix`.
+- Each of the next `n` lines describes a row, `matrix[i]`, and consists of `n` space-separated integers `matrix[i][j]`.
+
+
+### Constraints:
+
+- $-100 \le matrix[i][j] \le 100$
+
+### Output Format:
+
+- Return the absolute difference between the sums of the matrix's two diagonals as a single integer.
+
+---
+
+### Sample Input:
+
+```
+11 2 4
+4 5 6
+10 8 -12
+```
+
+### Sample Output:
+
+```
+15
+```
+
+---
+
+### Solution:
+
+- [Code](/src/challenges/05-diagonal-difference/diagonal-difference.ts)
+- [Tests](/src/challenges/05-diagonal-difference/test/diagonal-difference.test.ts)

src/challenges/05-diagonal-difference/diagonal-difference.ts

@@ -0,0 +1,28 @@
+export type Input = number[][];
+export type Output = number;
+
+/**
+ * Given a square matrix, calculate the absolute difference between the sums of its diagonals.
+ *
+ * @param matrix
+ */
+export const diagonalDifference = (matrix: Input): Output => {
+ const size = matrix.length;
+
+ let primarySum = 0;
+ let secondarySum = 0;
+
+ for (let i = 0; i < size; i++) {
+ for (let j = 0; j < size; j++) {
+ if (i === j) {
+ primarySum += matrix[i][j];
+ }
+
+ if (i + j === size - 1) {
+ secondarySum += matrix[i][j];
+ }
+ }
+ }
+
+ return Math.abs(primarySum - secondarySum);
+};

src/challenges/05-diagonal-difference/test/diagonal-difference.test.ts

@@ -0,0 +1,67 @@
+import { Input, diagonalDifference, Output } from "../diagonal-difference";
+
+type Cases = [Input, Output][];
+
+describe("Diagonal Difference", () => {
+ const cases: Cases = [
+ [
+ [
+ [11, 2, 4],
+ [4, 5, 6],
+ [10, 8, -12],
+ ],
+ 15,
+ ],
+ [
+ [
+ [1, 5, 6],
+ [3, 2, 7],
+ [8, 5, 1],
+ ],
+ 12,
+ ],
+ [
+ [
+ [1, 5, 6, 2],
+ [3, 2, 7, 9],
+ [8, 5, 1, 3],
+ [2, 6, 8, 9],
+ ],
+ 3,
+ ],
+ [
+ [
+ [2, 4, 5, 6],
+ [8, 3, 1, 3],
+ [7, 9, 4, 2],
+ [5, 8, 3, 6],
+ ],
+ 6,
+ ],
+ [
+ [
+ [1, 2, 3],
+ [4, 5, 6],
+ [7, 8, 9],
+ ],
+ 0,
+ ],
+ [
+ [
+ [-1, 1, -7, -8],
+ [-10, -8, -5, -2],
+ [0, 9, 7, -1],
+ [4, 4, -2, 1],
+ ],
+ 1,
+ ],
+ ];
+
+ test.each(cases)(
+ "for given matrix %j output should be %d",
+ (firstArg, expectedResult) => {
+ const result = diagonalDifference(firstArg);
+ expect(result).toEqual(expectedResult);
+ }
+ );
+});