Added ProjectEuler problem 8 with passed test cases

Project-Euler/Problem8.js

@@ -0,0 +1,26 @@
+// Problem: https://projecteuler.net/problem=8
+
+const largestAdjacentNumber = (grid, consecutive) => {
+  grid = grid.split('\n').join('');
+  const splitedGrid = grid.split("\n");
+  let largestProd = 0;
+
+  for (let row in splitedGrid) {
+    const currentRow = splitedGrid[row].split('').map(x => Number(x));
+
+    for (let i = 0; i < currentRow.length - consecutive; i++) {
+      const combine = currentRow.slice(i, i + consecutive);
+
+      if (!combine.includes(0)) {
+        const product = combine.reduce(function (a, b) {
+          return a * b
+        });
+
+        if (largestProd < product) largestProd = product;
+      }
+    }
+  }
+  return largestProd;
+}
+
+export { largestAdjacentNumber };

Project-Euler/test/Problem8.test.js

@@ -0,0 +1,104 @@
+import { largestAdjacentNumber } from '../Problem8';
+
+const grid1 = `73167176531330624919225119674426574742355349194934
+96983520312774506326239578318016984801869478851843
+85861560789112949495459501737958331952853208805511
+12540698747158523863050715693290963295227443043557
+66896648950445244523161731856403098711121722383113
+38991007832084782777189757278819047278899274961949
+30358907296290491560440772390713810515859307960866
+70172427121883998797908792274921901699720888093776
+65727333001053367881220235421809751254540594752243
+82834772897718748193457134085784719857638187485919
+53697817977846174064955149290862569321978468622482
+83972241375657056057490261407972968652414535100474
+82166370484403199890008895243450658541227588666881
+83247832478757285710958372981577583275832789327921
+17866458359124566529476545682848912883142607690042
+24219022671055626321111109370544217506941658960408
+84327878357761783787589375857378271083787811983779
+84580156166097919133875499200524063689912560717606
+05886116467109405077541002256983155200055935729725
+82347875831098357801578571807585817518287829189189`;
+
+const grid2 = `73167176531330624919225119674426574742355349194934
+96983520312774506326239578318016984801869478851843
+85861560789112949495459501737958331952853208805511
+12540698747158523863050715693290963295227443043557
+66896648950445244523161731856403098711121722383113
+62229893423380308135336276614282806444486645238749
+30358907296290491560440772390713810515859307960866
+70172427121883998797908792274921901699720888093776
+65727333001053367881220235421809751254540594752243
+52584907711670556013604839586446706324415722155397
+53697817977846174064955149290862569321978468622482
+83972241375657056057490261407972968652414535100474
+82166370484403199890008895243450658541227588666881
+16427171479924442928230863465674813919123162824586
+17866458359124566529476545682848912883142607690042
+24219022671055626321111109370544217506941658960408
+07198403850962455444362981230987879927244284909188
+84580156166097919133875499200524063689912560717606
+05886116467109405077541002256983155200055935729725
+71636269561882670428252483600823257530420752963450`;
+
+const grid3 = `89125732138957892357892768971807934878999818278898
+48327483578957875827583295789187588875238579887789
+74358275778171870973857835738758275210873583758279
+81347834738473878758758373857893758787772897580719
+81232847857895758758987587501087575387538183787098
+17047878395783578750837100983787587582797837508298
+42894789325732857893759187987487489748377578791989
+82147328972387832578327581919827382758932789798289
+83243289473847328974832947832748932472387895738978
+84738294738973289578753287582375238957573297892398
+29383748329748397483274832748327477575018978975289
+48327483758375846372864736476478364783647463278787
+73281473847832974328758975890189373857875875895898
+74328978748329789357389578329758329758937893758979
+81738957389579287598217589127589375893275987359889
+71890743894732897510875895783297591085738975837897
+10783974839479879857895789758975981735870175835789
+01494787857897583758975849758475107589754897589789
+09939858758919788017587897587387585775289757982898
+74718478978758758975897589789789798789178957789789`;
+
+const grid4 = `99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999
+99999999999999999999999999999999999999999999999999`;
+
+describe('checkLargestAdjacentNumberProduct', () => {
+  it('Random Example', () => {
+    const RESULT = largestAdjacentNumber(grid1, 13)
+    expect(RESULT).toBe(23514624000)
+  })
+  it('Problem statement Example', () => {
+    const RESULT = largestAdjacentNumber(grid2, 13)
+    expect(RESULT).toBe(23514624000)
+  })
+  it('Random Example 2', () => {
+    const RESULT = largestAdjacentNumber(grid3, 13)
+    expect(RESULT).toBe(580717154304)
+  })
+  it('Example with all 9', () => {
+    const RESULT = largestAdjacentNumber(grid4, 13)
+    expect(RESULT).toBe(2541865828329)
+  })
+})