/**
* Gets the "flip value" of setting this var to newValue. If setting var to newValue resulted in
* breaking two expressions and fixing one, the retval would be -1.
*
* @param val the variable to set
* @param newValue the value of the variable (1 for true, -1 for false)
*/
public int getFlipValue(int val, int newValue) {
int newVariable = 0;
int notVariable = 0;
int flipVal = 0;
if (val < 0 && newValue == -1) {
newVariable = val;
} else if (val < 0 && newValue == 1) {
newVariable = val * -1;
} else {
newVariable = val * newValue;
}
notVariable = -newVariable;
for (Clause c : clauses) {
int varSize = c.getVariables().size();
for (int i = 0; i < varSize; i++) {
int var = c.getVariables().get(i);
if (var == newVariable) {
flipVal++;
break;
} else if (c.isSatisfied() && c.getSatisfiedVar() == notVariable) {
flipVal--;
}
}
}
return flipVal;
}
/**
* Get all unsatisfied clauses
*
* @return
*/
public ArrayList<Clause> getUnsatisfied() {
ArrayList<Clause> retval = new ArrayList<Clause>();
for (Clause c : clauses) {
if (!c.isSatisfied()) {
retval.add(c);
}
}
return retval;
}
/**
* Returns true if flipping this variable breaks nothing, false otherwise
*
* @param val
* @param newValue
* @return
*/
public boolean isPositiveFlip(int val, int newValue) {
int newVariable = 0;
int notVariable = 0;
if (val < 0 && newValue == -1) {
newVariable = val;
} else if (val < 0 && newValue == 1) {
newVariable = val * -1;
} else {
newVariable = val * newValue;
}
notVariable = -newVariable;
for (Clause c : clauses) {
int varSize = c.getVariables().size();
for (int i = 0; i < varSize; i++) {
if (c.isSatisfied() && c.getSatisfiedVar() == notVariable) {
return false;
}
}
}
return true;
}
/**
* Sets the variable in the formula
*
* @param val the variable to set
* @param newValue the value of the variable (1 for true, -1 for false)
*/
public void setVariable(int val, int newValue) {
int newVariable = 0;
int notVariable = 0;
if (val < 0 && newValue == -1) {
newVariable = val;
} else if (val < 0 && newValue == 1) {
newVariable = val * -1;
} else {
newVariable = val * newValue;
}
notVariable = -newVariable;
for (Clause c : clauses) {
int varSize = c.getVariables().size();
for (int i = 0; i < varSize; i++) {
int var = c.getVariables().get(i);
if (var == newVariable) {
c.setSatisfiedVar(var);
break;
} else if (c.isSatisfied() && c.getSatisfiedVar() == notVariable) {
c.setSatisfiedVar(0);
}
}
}
}