题解 | #构建乘积数组#
构建乘积数组
https://www.nowcoder.com/practice/94a4d381a68b47b7a8bed86f2975db46
/**
* 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
*
* @param A int整型一维数组
* @return int整型一维数组
*/
export function multiply(A: number[]): number[] {
// write code here
const ascMul = [A[0]]
const descMul = [A[A.length - 1]]
for (let i = 1; i < A.length; i++) {
ascMul[i] = ascMul[i - 1] * A[i]
}
for (let i = 1; i < A.length; i++) {
descMul[i] = descMul[i - 1] * A[A.length - i - 1]
}
const B = []
B[0] = descMul[A.length - 2]
B[A.length - 1] = ascMul[A.length - 2]
for (let i = 1; i < A.length - 1; i++) {
B[i] = ascMul[i - 1] * descMul[A.length - i - 2]
}
return B
}
O(N)
O(N)
