알고리즘 문제 2

function findRange(num) {
    const numStr = num.toString();
    
    let min = 0;
    let max = 0;
    
    let changeIndex = 0;
    if(numStr[changeIndex] === '1') {
        changeIndex++;
        
        while(changeIndex < numStr.length && (numStr[changeIndex] === '0' || numStr[changeIndex] === '1' )) {
            changeIndex++;
        }
        min = numStr.replaceAll(numStr[changeIndex],'0');    
    } else {
        min = numStr.replaceAll(numStr[changeIndex],'1');    
    }    
    
    changeIndex = 0;
    if (numStr[changeIndex] === '9') {
        changeIndex++;
        
        while(changeIndex < numStr.length && numStr[changeIndex] === '9') {
            changeIndex++;
        }
    } 
    max = numStr.replaceAll(numStr[changeIndex],'9');    
    
    const result = Number(max) - Number(min);
    
    return result;
}