We are required to write a JavaScript function that takes in a string of any variable length that represents a number.
Our function is supposed to convert the number string to the corresponding letter string.
For example − If the number string is −
const str = '78956';
Then the output should be −
const output = 'ghief';
If the number string is −
const str = '12345';
Then the output string should be −
const output = 'lcde';
Notice how we didn't convert 1 and 2 to alphabets separately because 12 also represents an alphabet. So we have to consider this case while writing our function.
We, here, assume that the number string will not contain 0 in it, if it contains though, 0 will be mapped to itself.
Example
Let us write the code for this function −
const str = '12345'; const str2 = '78956'; const convertToAlpha = numStr => { const legend = '0abcdefghijklmnopqrstuvwxyz'; let alpha = ''; for(let i = 0; i < numStr.length; i++){ const el = numStr[i], next = numStr[i + 1]; if(+(el + next) <= 26){ alpha += legend[+(el + next)]; i++; } else{ alpha += legend[+el]; }; }; return alpha; }; console.log(convertToAlpha(str)); console.log(convertToAlpha(str2));
Output
And the output in the console will be −
lcde ghief