PWGHF: implement requested changes in old PR omegac xic (#6139)

Author: ZFederica

PWGHF/TableProducer/candidateCreatorXic0Omegac0.cxx

@@ -105,16 +105,21 @@ struct HfCandidateCreatorXic0Omegac0 {
 
   void init(InitContext const&)
   {
+    std::array<bool, 9> allProcesses = {doprocessNoCentToXiPi, doprocessCentFT0CToXiPi, doprocessCentFT0MToXiPi, doprocessNoCentToOmegaPi, doprocessCentFT0CToOmegaPi, doprocessCentFT0MToOmegaPi, doprocessNoCentToOmegaK, doprocessCentFT0CToOmegaK, doprocessCentFT0MToOmegaK};
+    if (std::accumulate(allProcesses.begin(), allProcesses.end(), 0) == 0) {
+      LOGP(fatal, "No process function enabled, please select one for at least one channel.");
+    }
+
     std::array<bool, 3> processesToXiPi = {doprocessNoCentToXiPi, doprocessCentFT0CToXiPi, doprocessCentFT0MToXiPi};
-    if (std::accumulate(processesToXiPi.begin(), processesToXiPi.end(), 0) != 1) {
+    if (std::accumulate(processesToXiPi.begin(), processesToXiPi.end(), 0) > 1) {
       LOGP(fatal, "One and only one ToXiPi process function must be enabled at a time.");
     }
     std::array<bool, 3> processesToOmegaPi = {doprocessNoCentToOmegaPi, doprocessCentFT0CToOmegaPi, doprocessCentFT0MToOmegaPi};
-    if (std::accumulate(processesToOmegaPi.begin(), processesToOmegaPi.end(), 0) != 1) {
+    if (std::accumulate(processesToOmegaPi.begin(), processesToOmegaPi.end(), 0) > 1) {
       LOGP(fatal, "One and only one process ToOmegaPi function must be enabled at a time.");
     }
-    std::array<bool, 9> processesToOmegaK = {doprocessNoCentToOmegaK, doprocessCentFT0CToOmegaK, doprocessCentFT0MToOmegaK};
-    if (std::accumulate(processesToOmegaK.begin(), processesToOmegaK.end(), 0) != 1) {
+    std::array<bool, 3> processesToOmegaK = {doprocessNoCentToOmegaK, doprocessCentFT0CToOmegaK, doprocessCentFT0MToOmegaK};
+    if (std::accumulate(processesToOmegaK.begin(), processesToOmegaK.end(), 0) > 1) {
       LOGP(fatal, "One and only one process ToOmegaK function must be enabled at a time.");
     }