package main
import "fmt"
func pivotIndex(nums []int , n int)(isPivotIndex bool, idx int) {
// in the first loop compute the summary of all numbers
var sum = 0
for i := 0; i < n; i++ {
sum += nums[i]
}
// in the second loop find the index of pivot
var left_sum = 0
for i := 0; i < n; i++ {
var right_sum = sum - left_sum - nums[i]
if left_sum == right_sum {
return true, i
}
left_sum += nums[i]
}
return false, -1
}
func pivotIndexHelper(nums []int , n int) {
isPivotIndex, idx := pivotIndex(nums, n)
if isPivotIndex {
fmt.Printf("yes, pivot index is %d \n", idx)
} else {
fmt.Printf("no \n")
}
}
func main() {
pivotIndexHelper([]int {1, 7, 3, 6, 5, 6}, 6)
pivotIndexHelper([]int {1, 2, 3}, 3)
}
最后的执行结果如下：
yes, pivot index is 3
no
