merge sorted DSA

// mergeSortedArrays([0,3,4,31],  [4,6,30])

// if any one is empty return the other

// once at the end append remaining
// [1] [2,3,4]

type numArrays =  number[];

function  mergeSortedArrays(first: numArrays  ,  second:  numArrays):numArrays{
    if (first.length == 0  ||  second.length ==  0){
        return first.length <  second.length?  first :  second;
    }
    
    let store: number[] =  [];
    
    let firstPtr =  0;
    let secondPtr = 0;
    
    while (firstPtr < first.length && secondPtr <  second.length) {
        const firstElem = first[firstPtr];
        const secondElem =  second[secondPtr];
        
        if(firstElem <=  secondElem){
            store.push(firstElem);
            firstPtr += 1;
        }else{
            store.push(secondElem);
            secondPtr += 1;
        }
        
    }
    
    
    if(firstPtr ===  first.length){
        const remaining =  second.slice(secondPtr);
        store =  store.concat(remaining);
    }else{
        const remaining =  first.slice(firstPtr);
        store =  store.concat(remaining);
    }
    
    return store;
}

console.log(mergeSortedArrays([0,3,4,31],  [4,6,30]));