feat(examples): added check for overflow/underflow

[MalekLahbib]

Contributors' checklist...

• Added new tests, or not needed, or not feasible
• Provided an example (e.g. screenshot) to aid review or the PR is self-explanatory
• Updated the official documentation or not needed
• No breaking changes were made, or a BREAKING CHANGE: xxx message was included in the description
• Added references to related issues and PRs
• Provided any useful hints for running manual tests
• Added new benchmarks to generated graphs, if any. More info here.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 60.92%. Comparing base (01d9e8d) to head (7e174be).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2874   +/-   ##
=======================================
  Coverage   60.91%   60.92%           
=======================================
  Files         564      564           
  Lines       75273    75273           
=======================================
+ Hits        45855    45859    +4     
  Misses      26047    26047           
+ Partials     3371     3367    -4     

Flag	Coverage Δ
contribs/gnodev	61.46% <ø> (ø)
contribs/gnofaucet	14.46% <ø> (-0.86%)	⬇️
gno.land	67.17% <ø> (ø)
gnovm	65.77% <ø> (ø)
misc/genstd	80.54% <ø> (ø)
misc/logos	20.23% <ø> (+0.35%)	⬆️
tm2	62.10% <ø> (+<0.01%)	⬆️

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