veriPB : try to use saturation in the proof only when necessary

org.sat4j.pb/src/main/java/org/sat4j/pb/constraints/pb/ConflictMap.java

@@ -743,10 +743,10 @@ public class ConflictMap extends MapPb implements IConflict {
 
     protected BigInteger saturation(BigInteger[] coefs, BigInteger degree,
             IWatchPb wpb) {
-        listener.saturateReason();
         assert degree.signum() > 0;
         BigInteger degreeResult = degree;
         boolean isMinimumEqualsToDegree = true;
+        boolean useSaturation = false;
         int comparison;
         for (int i = 0; i < coefs.length; i++) {
             comparison = coefs[i].compareTo(degree);
@@ -756,6 +756,9 @@ public class ConflictMap extends MapPb implements IConflict {
                             .subtract(coefs[i]);
                     this.possReducedCoefs = this.possReducedCoefs.add(degree);
                 }
+                if (!(degree.equals(coefs[i]))) {
+                    useSaturation = true;
+                }
                 coefs[i] = degree;
             } else if (comparison < 0 && coefs[i].signum() > 0) {
                 isMinimumEqualsToDegree = false;
@@ -778,6 +781,9 @@ public class ConflictMap extends MapPb implements IConflict {
             }
             listener.divideReason(degree);
         }
+        if (useSaturation) {
+            listener.saturateReason();
+        }
         return degreeResult;
     }
 

org.sat4j.pb/src/main/java/org/sat4j/pb/constraints/pb/MapPb.java

@@ -179,12 +179,13 @@ public class MapPb implements IDataStructurePB {
     }
 
     public BigInteger saturation() {
-        listener.saturateConflict();
         assert this.degree.signum() > 0;
         BigInteger minimum = this.degree;
+        boolean useSaturation = false;
         for (int ind = 0; ind < size(); ind++) {
             assert this.weightedLits.getCoef(ind).signum() >= 0;
             if (this.degree.compareTo(this.weightedLits.getCoef(ind)) < 0) {
+                useSaturation = true;
                 changeCoef(ind, this.degree);
             }
             assert this.weightedLits.getCoef(ind).signum() >= 0;
@@ -200,7 +201,9 @@ public class MapPb implements IDataStructurePB {
                 changeCoef(ind, BigInteger.ONE);
             }
         }
-
+        if (useSaturation) {
+            listener.saturateConflict();
+        }
         return this.degree;
     }