[PWGLF,PWGMM] mftReassociationValidation.cxx : add flexibility to save memory, implement cuts for further studies

[AlexianL]

No description provided.

[github-actions]

O2 linter results: ❌ 0 errors, ⚠️ 0 warnings, 🔕 0 disabled

[alibuild]

Error while checking build/O2Physics/code-check for 9475345 at 2026-07-15 16:37:

## sw/BUILD/O2Physics-code-check-latest/log
--
========== List of issues found ==========
++ echo 'Found 50 errors and 0 warnings.'
Found 50 errors and 0 warnings.
++ [[ 50 -gt 0 ]]
++ cat /sw/BUILD/9dbe08387854b85d24c86f7f2d6d7108b87f4215/O2Physics-code-check/errors.txt
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:244:18: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:245:18: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:246:18: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:247:18: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:248:32: error: variable 'recoVtxX' is non-const and globally accessible, consider making it const [cppcoreguidelines-avoid-non-const-global-variables,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:249:32: error: variable 'recoVtxY' is non-const and globally accessible, consider making it const [cppcoreguidelines-avoid-non-const-global-variables,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:250:32: error: variable 'recoVtxZ' is non-const and globally accessible, consider making it const [cppcoreguidelines-avoid-non-const-global-variables,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:251:32: error: variable 'recoMultiplicity' is non-const and globally accessible, consider making it const [cppcoreguidelines-avoid-non-const-global-variables,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:252:32: error: variable 'recoNumContrib' is non-const and globally accessible, consider making it const [cppcoreguidelines-avoid-non-const-global-variables,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:253:32: error: variable 'recoMcCollisionId' is non-const and globally accessible, consider making it const [cppcoreguidelines-avoid-non-const-global-variables,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:254:32: error: variable 'recoMcCollBestCollisionIndex' is non-const and globally accessible, consider making it const [cppcoreguidelines-avoid-non-const-global-variables,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:256:8: error: constructor does not initialize these fields: pdg, ccdb [cppcoreguidelines-pro-type-member-init,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:332:20: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:423:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:435:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:449:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:460:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:521:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:532:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:543:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:554:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:567:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:632:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:643:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:654:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:665:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:678:7: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:703:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:741:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:766:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:789:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:802:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:817:5: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:867:45: error: the parameter 'collision' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:899:56: error: the parameter 'track' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:938:5: error: use auto when initializing with a cast to avoid duplicating the type name [modernize-use-auto,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:938:39: error: do not use static_cast to downcast from a base to a derived class; use dynamic_cast instead [cppcoreguidelines-pro-type-static-cast-downcast,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:939:23: error: do not implicitly decay an array into a pointer; consider using gsl::array_view or an explicit cast instead [cppcoreguidelines-pro-bounds-array-to-pointer-decay,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:1189:33: error: redundant boolean literal supplied to boolean operator [readability-simplify-boolean-expr,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:1206:7: error: uninitialized record type: 'dcaInfOrig' [cppcoreguidelines-pro-type-member-init,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:1268:33: error: redundant boolean literal supplied to boolean operator [readability-simplify-boolean-expr,-warnings-as-errors]
PWGMM/Mult/Tasks/mftReassociationValidation.cxx:1322:7: error: uninitialized record type: 'dcaInfOrig' [cppcoreguidelines-pro-type-member-init,-warnings-as-errors]
[0 more errors; see full log]

Full log here.