1652. 拆炸弹.md

1652. 拆炸弹

/**
 * @param {number[]} code
 * @param {number} k
 * @return {number[]}
 */
var decrypt = function (code, k) {
    return code.map((value, index) => {
        let leftIndex, rightIndex;
        if (k > 0) {
            leftIndex = index + 1;
            rightIndex = index + 1 + k;
        } else if (k < 0) {
            leftIndex = index + k;
            rightIndex = index;
        } else {
            leftIndex = rightIndex = index;
        }
        return sum(code, leftIndex, rightIndex);
    })
};
// 计算array在区间[leftIndex, rightIndex)的和
function sum(array, leftIndex, rightIndex) {
    const { length } = array;
    let count = rightIndex - leftIndex,
        sum = 0;
    while (count-- > 0) {
        leftIndex = (leftIndex + length) % length;
        sum += array[leftIndex];
        leftIndex++;
    }
    return sum;
}