added both solve power function and both tests

src/mathString.test.ts

@@ -24,6 +24,7 @@ const input: string[] = [
   '1*2/4*6+4*3',
   '1-+-+--+2',
   '1+++2----3--+-+4',
+  '1+2^3+2^(4^2+7)',
 ];
 const faultInput = [
   '1**1*1***2',
@@ -70,6 +71,7 @@ describe('solve phrases math', () => {
     expect(solve(input[8])).toBe('15');
     expect(solve(input[5])).toBe('-3');
     expect(solve(input[4])).toBe('2');
+    expect(solve(input[11])).toBe('8388617');
   });
 });
 describe('detect fault input', () => {

src/regulaExpersions.ts

@@ -2,14 +2,15 @@ export const mathSigns = {
   multiplication: '*',
   divisin: '/',
   summation: '+',
-  subtraction: '-'
+  subtraction: '-',
+  power: '^',
 };
 const numRegString: string = '[+-]?\\d*\\.?\\d+(e[+-]?\\d+)?';
 export const numberRegExp: RegExp = new RegExp(`${numRegString}`, 'g');
 export const betweenParenthesesRegExp: RegExp = new RegExp(
   `\\(${numRegString}([\\${mathSigns.summation}\\${mathSigns.subtraction}\\${
     mathSigns.multiplication
-  }\\${mathSigns.divisin}]${numRegString})*\\)`,
+  }\\${mathSigns.divisin}\\${mathSigns.power}]${numRegString})*\\)`,
   'g'
 );
 export const divisionRegExp: RegExp = new RegExp(
@@ -26,3 +27,7 @@ export const summationOrSubtractionRegExp: RegExp = new RegExp(
   }]${numRegString}`,
   'g'
 );
+export const powerRegExp: RegExp = new RegExp(
+  `${numRegString}\\^${numRegString}`,
+  'g'
+);

src/selectModules.ts

@@ -3,6 +3,7 @@ import {
   divisionRegExp,
   multiplicationRegExp,
   numberRegExp,
+  powerRegExp,
   summationOrSubtractionRegExp
 } from './regulaExpersions';
 import { removeSpacesFromInput } from './utility';
@@ -26,3 +27,6 @@ export const selectDivisionPharse = (input: string) => {
 export const selectSummationOrSubtractionPhrase = (input: string) => {
   return input.match(summationOrSubtractionRegExp);
 };
+export const selectPowerPhrase = (input: string) => {
+  return input.match(powerRegExp);
+};

src/solveModules.ts

@@ -4,6 +4,7 @@ import {
   selectMultiplicationPhrase,
   selectNumbers,
   selectParantheses,
+  selectPowerPhrase,
   selectSummationOrSubtractionPhrase
 } from './selectModules';
 import { convertSpecialChar } from './utility';
@@ -22,7 +23,8 @@ export const solveBetweenParantheses = (input: string): string => {
 };
 export const solveMathPhrases = (phrase: string) => {
   let result = solveSevralPositiveAndNegativeSings(phrase);
-  result = solveDivisionPharse(phrase);
+  result = solvePowerPhrase(result);
+  result = solveDivisionPharse(result);
   result = solveMultiplicationPhrase(result);
   result = solveSummationOrSubtractionPhrase(result);
   result = result.replace(/[()]/g, '');
@@ -106,3 +108,21 @@ export const solveSevralPositiveAndNegativeSings = (phrase: string): string => {
   }
   return phrase;
 };
+export const solvePowerPhrase = (phrase: string): string => {
+  const powerPhrase = selectPowerPhrase(phrase);
+  if (!powerPhrase) {
+    return phrase;
+  }
+  powerPhrase.forEach(phr => {
+    const _result = solvePower(phr);
+    phrase = phrase.replace(phr, _result);
+  });
+  return solvePowerPhrase(phrase);
+};
+export const solvePower = (phr: string): string => {
+  const numbers = selectNumbers(phr)!;
+  const num1 = +numbers[0];
+  const num2 = +numbers[1];
+  const result = Math.pow(num1, num2);
+  return result > 0 ? `+${result}` : result.toString();
+};