#CCBCHHAI0000030. Dừng khi ba lần đúng liên tiếp (Three Consecutive Successes)

Dừng khi ba lần đúng liên tiếp (Three Consecutive Successes)

Three Consecutive Successes

Source: Phước Hưng OJ

Version: Phuoc Hung OJ Extended

Problem Statement

Read a stream of 0/1 results. One denotes success; zero denotes failure and resets the current run of successes. Stop at the first occurrence of three consecutive ones, and print the number of results read.

Input

A sequence of zeros and ones with at least one run of three consecutive ones. The final integer completes the first such run; nothing follows.

Output

Print the number of reads including the third 1 completing the first run.

Subtasks

  • Subtask 1 (20%): At most 88 values.
  • Subtask 2 (30%): At most 100100 values.
  • Subtask 3 (50%): At most 100000100000 values.

Examples

Example 1

Input

1 1 0 1 1 1

Output

6

Explanation

Initial ones form a run of length two, then zero resets it. The final three ones complete at read six.

Example 2

Input

1 1 1

Output

3

Explanation

The first three results are ones; the first triple completes at read three.