Wave 2 batch 2a: mermaid in problems 9, 15, 16, 17 #11

	name: Notify Blog

	# Fires a repository_dispatch event at shiningflash/shiningflash.github.io
	# whenever problems or PROBLEMS.md change on main, so the blog's
	# sync-practice workflow runs and the new content goes live within ~1 minute.

	on:
	push:
	branches: [main]
	paths:
	- "problems/**"
	- "PROBLEMS.md"
	- "scripts/build_index.py"

	workflow_dispatch:

	jobs:
	dispatch:
	runs-on: ubuntu-latest
	steps:
	- name: Dispatch to blog
	env:
	# A fine-grained PAT with "Contents: write" on shiningflash.github.io.
	# Add it as a repo secret named BLOG_DISPATCH_TOKEN.
	GH_TOKEN: ${{ secrets.BLOG_DISPATCH_TOKEN }}
	run: \|
	if [ -z "$GH_TOKEN" ]; then
	echo "BLOG_DISPATCH_TOKEN secret not set — skipping dispatch."
	echo "Add it under Settings → Secrets and variables → Actions."
	exit 0
	fi
	curl -fsSL -X POST \
	-H "Accept: application/vnd.github+json" \
	-H "Authorization: Bearer $GH_TOKEN" \
	-H "X-GitHub-Api-Version: 2022-11-28" \
	https://api.github.com/repos/shiningflash/shiningflash.github.io/dispatches \
	-d '{"event_type":"practice-problems-updated","client_payload":{"source_repo":"${{ github.repository }}","sha":"${{ github.sha }}"}}'
	echo "Dispatched practice-problems-updated to blog."

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