modified volume_matching method by Andrea Giacobbi: compute statistic iteratively

[erikposchivo]

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Summary

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[codacy-production]

Not up to standards ⛔

🔴 Issues 3 minor

Alerts:
⚠ 3 issues (≤ 0 issues of at least minor severity)

Results:
3 new issues

Category	Results
UnusedCode	2 minor
CodeStyle	1 minor

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🟢 Metrics 6 complexity · 0 duplication

Metric	Results
Complexity	6
Duplication	0

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