Sum with Ignored Sections

Background

Congcong is processing a list of integers. He needs to calculate the sum of these numbers, but with a special rule: if he encounters the number $6$, he must ignore all numbers from $6$ up to and including the next $7$. Congcong asks for your help to write a program to complete this task.

Problem Description

Calculate the sum of numbers in an array, but ignore sections of numbers starting with a $6$ and extending to the next $7$ (inclusive of both $6$ and $7$). It is guaranteed that every $6$ will be followed by at least one $7$. If the array contains no numbers, return $0$.

Input Format

Input is given from standard input in the following format.

nums (an array of integers)

Output Format

Output is printed to standard output in the following format.

sum (the calculated sum)

Sample

[1 2 2]

5

[1 2 2 6 99 99 7]

5

[1 1 6 7 2]

4

Sample Explanation

Sample 1: [1 2 2]. There are no $6$s or $7$s in the array, so the sum is $1 + 2 + 2 = 5$.

Sample 2: [1 2 2 6 99 99 7]. The section from the first $6$ to the next $7$ (i.e., 6 99 99 7) is ignored. Thus, the sum is $1 + 2 + 2 = 5$.

Sample 3: [1 1 6 7 2]. The section from $6$ to $7$ (i.e., 6 7) is ignored. Thus, the sum is $1 + 1 + 2 = 4$.

Constraints

Time limit: $1$ second, Memory limit: $1024$ KiB for each test case.