The Decision Control Structure Decisions

In the programs written in Chapter 1 we have used sequence control structure in which the various steps are executed sequentially, i.e. in the same order in which they appear in the program. In fact to execute the instructions sequentially, we don’t have to do anything at all. By default the instructions in a program are executed sequentially. However, in serious programming situations, seldom do we want the instructions to be executed sequentially. Many a times, we want a set of instructions to be executed in one situation, and an entirely different set of instructions to be executed in another situation. This kind of situation is dealt in C programs using a decision control instruction. As mentioned earlier, a decision control instruction can be implemented in C using:

(a) The if statement 

(b)The if-else statement 

(c)The conditional operators

Now let us learn each of these and their variations in turn.