Develop a pseudocode algorithm to build an expression tree from a prefix expression.
Create an expressiontree stack
Create an operator stack
While there is input
```
{
get the next term
if the term is an operand
{
create a node object containing the operand
push it on the expression tree stack
}
else if the term is an operator
{
push it on the operator stack
}
}
While the operator stack is not empty
{
pop one operator from the operator stack
pop two nodes from the expression tree stack
create a new node object containing the operator and pointing to the two nodes
push the resulting node onto the expression tree stack
}
```
At the conclusion of this algorithm, there should be a single node on the expression tree stack and it will be the root of the expression tree.
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