# 3.2. Worked Example: If-Else Statements¶

Subgoals for Evaluating Selection Statements

1. Diagram which statements go together.

2. For if-statement, determine whether expression is true or false.

3. If true, follow true branch. If false, follow else branch (OR do nothing if there is no else branch).

You can watch this video or read through the content below it.

Given the following declarations:

```int alpha = 2, beta = 1, delta = 3, eta = 0, gamma = 0;

double omega = 2.5, theta = -1.3, kappa = 3.0, lambda = 0.0, rho = 0.0;
```

Evaluate these statements and determine the value of all variables used.

```if (alpha > delta)
eta = alpha + 2;
else
gamma = alpha + 5;
```

SG1: Diagram which statements go together.

If no { } are present, then by default all if and else branches have only a single statement:

```if (alpha > delta)
eta = alpha +2;
else
gamma = alpha + 5;
```

SG2: For if statement, determine whether true or false

First we evaluate (alpha > delta):

`(2 > 3)` is FALSE

SG3: If true, follow true branch. If false, follow else branch (OR do nothing if there is no else branch).

The condition is FALSE so we execute the else branch:

gamma = alpha + 5

= 2 + 5 = 7

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