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# minimize(+Goal, ?Template, ?Solution, ?C)

Find the solution of Goal that minimizes C, and unify the minimized Template with Solution.
+Goal
A callable term.
?Template
A term containing all or some of Goal's variables
?Solution
Term to be unified with the minimized Template
?C
A linear term or a list of linear terms.

## Description

A solution of the goal Goal is found that minimizes the value of C. The solution is found using the branch and bound method. Whenever a better solution is found, the upper cost bound is tightened and the search for a better solution continues. Every time a new better solution is found, the event 280 is raised, its default handler prints the current cost.

Solutions will be unified with a copy of Template where the variables are replaced with their minimized values. Typically, the Template will contain all or a subset of Goal's variables.

minimize/2 can be written in terms of minimize/4 as follows:

```	minimize(Goal, Cost) :-
minimize(Goal, Goal, Goal, Cost).
```

### Fail Conditions

Fails if there is no solution to Goal.

No.

## Examples

```    % Find the minimal C and bind X to the corresponding value
[eclipse]: X::1..3, C #= 3-X, minimize(indomain(X), X, X, C).
Found a solution with cost 2
Found a solution with cost 1
Found a solution with cost 0
X = 3
C = 0
yes.

% Find the minimal C and don't bind anything
[eclipse]: X::1..3, C #= 3-X, minimize(indomain(X), [], [], C).
Found a solution with cost 2
Found a solution with cost 1
Found a solution with cost 0
X = X{[1..3]}
C = C{[0..2]}

Delayed goals:
-3 + X{[1..3]} + C{[0..2]}#=0
yes.

% Find the minimal C and return it in MinC. Don't bind X or C.
[eclipse]: X::1..3, C #= 3-X, minimize(indomain(X), C, MinC, C).
Found a solution with cost 2
Found a solution with cost 1
Found a solution with cost 0
X = X{[1..3]}
MinC = 0
C = C{[0..2]}

Delayed goals:
-3 + X{[1..3]} + C{[0..2]}#=0
yes.

```

## See Also

min_max / 2, min_max / 4, min_max / 5, min_max / 6, min_max / 8, minimize / 2, minimize / 5, minimize / 6, minimize / 8, minimize_bound_check / 0