#!/usr/bin/env python
from common import Report, ReportList, is_safe, parse


def report_remove(report: Report, index: int) -> Report:
    return report[:index] + report[index + 1 :]


def is_safe_dampened(report: Report) -> bool:
    return is_safe(report) or any(map(is_safe, map(lambda x: report_remove(report, x[0]), enumerate(report))))


def solve(input: ReportList) -> int:
    return len(list(filter(is_safe_dampened, input)))


def main():
    print(solve(parse("input")))


if __name__ == "__main__":
    main()