How to divide histogram bars into successes and failures for robot journeys?

Question

For task 4 of this assignment https://github.com/hawesie/oxnet-science/blob/main/notebooks/robot_navigation_statistics.ipynb

it asks that the bars of the histogram generated by

# first 10 edge ids

top_edge_ids = edge_ids[:10]

# first 10 counts

top_counts = counts[:10]

plt.bar(top_edge_ids, top_counts)

plt.ylabel('Count')

plt.title('Top 10 edge data counts')

plt.xticks(rotation=90)

be divided into successes and failures; how do I ascertain the number of successes and failures from the navigation data and how would i use this to divide the bars?

any help appreciated, thanks