 The most common statement is an "expression statement", consisting of an expression to be evaluated, followed by a semicolon; as a side effect of the evaluation, functions may be called and variables may be assigned new values.To modify the normal sequential execution of statements, C provides several control-flow statements identified by reserved keywords.Structured programming is supported by codice_60(-codice_61) conditional execution and by codice_62-codice_4, codice_4, and codice_2 iterative execution (looping).