0043【Edabit ★☆☆☆☆☆】【递归求字符串的长度】Recursion: Length of a String

language_fundamentals recursion strings

Instructions

Write a function that returns the length of a string. Make your function recursive.

Examples

length("apple") // 5
length("make") // 4
length("a") // 1
length("") // 0

Notes

• N/A

Solutions

function length(str) {if(str.length == 0){return 0;}return 1 + length(str.slice(1));
}

TestCases

let Test = (function(){return {assertEquals:function(actual,expected){if(actual !== expected){let errorMsg = `actual is ${actual},${expected} is expected`;throw new Error(errorMsg);}},assertSimilar:function(actual,expected){if(actual.length != expected.length){throw new Error(`length is not equals, ${actual},${expected}`);}for(let a of actual){if(!expected.includes(a)){throw new Error(`missing ${a}`);}}}}
})();Test.assertEquals(length('shipment'), 8)
Test.assertEquals(length('apple'), 5)
Test.assertEquals(length('make'), 4)
Test.assertEquals(length('a'), 1)
Test.assertEquals(length(''), 0)