pascal's triangle

pascal.js

function pascalRow(row) {
    let prev = [];
    let curr = [];
    for (let i = 1; i <= row; i++) {
        prev = curr;
        curr = [];
        if (prev.length === 0) {
            curr = [1];
            continue;
        } 

        for (let j=0; j<= prev.length; j++) {
            val1 = prev[j-1] || 0;
            val2 = prev[j] || 0;
            curr.push(val1+val2);
        }
    }

    return curr;
}