1.1 KiB
1.1 KiB
title | localeTitle |
---|---|
Sum square difference | 和方差 |
问题6:求和方差
方法:
解:
function sumSquareDifference(n) {
const sumOfN = (n*(n+1))/2;
const sumOfNSquare = (n*(n+1)*(2*n+1))/6;
//** is exponentaial operator added in ES7, it's equivalent to Math.pow(num, 2)`
return (sumOfN ** 2) - sumOfNSquare;
}