Some embodiments of the present invention provide a system that tests a software program. During operation, the system creates a behavioral model of the software program using branches, decisions, and options. Next, the system applies a weight assignment technique to the behavioral model to create a set of global identifiers (IDs), which correspond to test cases of the behavioral model. The system then generates a test case from the behavioral model and executes the test case on the software program. Finally, the system analyzes an output of the executed test case to determine a validity of the software program.