47 lines
1.3 KiB
JavaScript
47 lines
1.3 KiB
JavaScript
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const { AssertionError } = require('assert')
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const assert = require('assert')
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const power_for = function (base, exponent) {
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let result = 1
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for (let count = 0; count < exponent; count++) {
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result *= base
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}
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return result
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}
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const power_rec = function (base, exponent) {
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if(exponent == 0) {
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return 1;
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}
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return base * power_rec(base, exponent - 1)
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}
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const power_rec_opt = function (base, exponent) {
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if(exponent == 0) {
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return 1;
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}
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else if(exponent % 2 == 0) { //gerade
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let value = power_rec_opt(base, exponent / 2)
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return value * value
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} else { //ungerade
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return base * power_rec_opt(base, exponent - 1)
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}
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}
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const power = function(base, exponent){
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assert.ok(Number.isInteger(base), "Exponent is not an Integer")
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assert.ok(Number.isInteger(exponent), "Exponent is not an Integer")
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assert.ok(base >= 0)
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assert.ok(exponent >= 0)
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return power_rec_opt(base, exponent)
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}
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//console.log("With for Loop: " + power_for(2, 10)) // → 1024
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//console.log("With recursion: " + power_rec(2, 10)) // → 1024
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//console.log("With recursion optimized: " + power_rec_opt(2, 10)) // → 1024
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// console.log(power(2, 10)) // → 1024
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// console.log(power(2, 2.5)) // !! AssertionError
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module.exports = { power }
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