[PWGHF] taskFlow.cxx : fix centrality, fix mcGen, add outer and inner FT0 selections and other small changes

[AlexianL]

No description provided.

[github-actions]

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

[vkucera]

@AlexianL I noticed that you fix the formatting issues with additional commits. Please note that this can be fully automated with the pre-commit hook or you can just merge the formatting PR, as explained in the contribution guidelines.

[AlexianL]

@AlexianL I noticed that you fix the formatting issues with additional commits. Please note that this can be fully automated with the pre-commit hook or you can just merge the formatting PR, as explained in the contribution guidelines.

Hi, thanks for the reminder! I knew about them but I forgot to install the pre-commit hook after I re-installed O2Physics completely few days ago

[alibuild]

Error while checking build/O2Physics/code-check for 621b4f6 at 2026-10-07 22:43:

## sw/BUILD/O2Physics-code-check-latest/log
--
========== List of issues found ==========
++ echo 'Found 1 errors and 42 warnings.'
Found 1 errors and 42 warnings.
++ [[ 1 -gt 0 ]]
++ cat /sw/BUILD/6ef5b47eddeef6d10731b2772c6f72d8b5303f77/O2Physics-code-check/errors.txt
PWGHF/HFC/Tasks/taskFlow.cxx:1925:15: error: Variable 'rad' with floating point type 'double' should not be used as a loop counter [clang-analyzer-security.FloatLoopCounter,-warnings-as-errors]
++ [[ 42 -gt 0 ]]
++ cat /sw/BUILD/6ef5b47eddeef6d10731b2772c6f72d8b5303f77/O2Physics-code-check/warnings.txt
PWGHF/HFC/Tasks/taskFlow.cxx:117:1: warning: initial values in enum 'FT0InnerOrOuter' are not consistent, consider explicit initialization of all, none or only the first enumerator [readability-enum-initial-value]
PWGHF/HFC/Tasks/taskFlow.cxx:199:18: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:200:18: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:201:18: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:202:18: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:203:18: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:218:18: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:311:59: warning: 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]
PWGHF/HFC/Tasks/taskFlow.cxx:370:35: warning: initializer for member 'cstFT0RelGain' is redundant [readability-redundant-member-init]
PWGHF/HFC/Tasks/taskFlow.cxx:537:5: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:549:5: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:567:5: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:623:7: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:633:7: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:835:9: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:893:9: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:926:9: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:983:9: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGHF/HFC/Tasks/taskFlow.cxx:1326:9: warning: do not use 'else' after 'return' [readability-else-after-return]
PWGHF/HFC/Tasks/taskFlow.cxx:1341:9: warning: do not use 'else' after 'return' [readability-else-after-return]
PWGHF/HFC/Tasks/taskFlow.cxx:1361:60: warning: redundant boolean literal supplied to boolean operator [readability-simplify-boolean-expr]
PWGHF/HFC/Tasks/taskFlow.cxx:1368:60: warning: redundant boolean literal supplied to boolean operator [readability-simplify-boolean-expr]
PWGHF/HFC/Tasks/taskFlow.cxx:1375:60: warning: redundant boolean literal supplied to boolean operator [readability-simplify-boolean-expr]
PWGHF/HFC/Tasks/taskFlow.cxx:1382:58: warning: redundant boolean literal supplied to boolean operator [readability-simplify-boolean-expr]
PWGHF/HFC/Tasks/taskFlow.cxx:1460:23: warning: narrowing conversion from 'float' to 'int' [bugprone-narrowing-conversions]
PWGHF/HFC/Tasks/taskFlow.cxx:1790:23: warning: narrowing conversion from 'Double_t' (aka 'double') to 'int' [bugprone-narrowing-conversions]
PWGHF/HFC/Tasks/taskFlow.cxx:2026:23: warning: narrowing conversion from 'Double_t' (aka 'double') to 'int' [bugprone-narrowing-conversions]
PWGHF/HFC/Tasks/taskFlow.cxx:2223:23: warning: narrowing conversion from 'Double_t' (aka 'double') to 'int' [bugprone-narrowing-conversions]
PWGHF/HFC/Tasks/taskFlow.cxx:2492:23: warning: narrowing conversion from 'Double_t' (aka 'double') to 'int' [bugprone-narrowing-conversions]
PWGHF/HFC/Tasks/taskFlow.cxx:2643:23: warning: narrowing conversion from 'Double_t' (aka 'double') to 'int' [bugprone-narrowing-conversions]
PWGHF/HFC/Tasks/taskFlow.cxx:2711:23: warning: narrowing conversion from 'Double_t' (aka 'double') to 'int' [bugprone-narrowing-conversions]
PWGHF/HFC/Tasks/taskFlow.cxx:2843:9: warning: do not use 'else' after 'return' [readability-else-after-return]
PWGHF/HFC/Tasks/taskFlow.cxx:2905:9: warning: do not use 'else' after 'return' [readability-else-after-return]
PWGHF/HFC/Tasks/taskFlow.cxx:2969:9: warning: do not use 'else' after 'return' [readability-else-after-return]
PWGHF/HFC/Tasks/taskFlow.cxx:3040:9: warning: do not use 'else' after 'return' [readability-else-after-return]
PWGHF/HFC/Tasks/taskFlow.cxx:3132:9: warning: do not use 'else' after 'return' [readability-else-after-return]
PWGHF/HFC/Tasks/taskFlow.cxx:3403:22: warning: narrowing conversion from 'double' to 'int' [bugprone-narrowing-conversions]
PWGHF/HFC/Tasks/taskFlow.cxx:4173:22: warning: narrowing conversion from 'unwrap_t<float>' (aka 'float') to 'int' [bugprone-narrowing-conversions]
PWGHF/HFC/Tasks/taskFlow.cxx:4565:24: warning: narrowing conversion from 'unwrap_t<float>' (aka 'float') to 'int' [bugprone-narrowing-conversions]
[0 more errors; see full log]

Full log here.