a. break and continue
Two keywords that are very important to looping are break and continue.
The break command will exit the most immediately surrounding loop regardless of what the conditions of the loop are. Break is useful if we want to exit a loop under special circumstances.
#include
void main()
{
int a;
printf("Pick a number from 1 to 4:\n");
scanf("%d", &a); switch (a)
{
case 1:
printf("You chose number 1\n");
break;
case 2:
printf("You chose number 2\n");
break;
case 3:
printf("You chose number 3\n");
break;
case 4:
printf("You chose number 4\n");
break;
default: printf("That's not 1,2,3 or 4!\n");
}
getch();
Continue is another keyword that controls the flow of loops. If we are executing a loop and hit a continue statement, the loop will stop its current iteration, update itself (in the case of for loops) and begin to execute again from the top. Essentially, the continue statement is saying "this iteration of the loop is done; let's continue with the loop without executing whatever code comes after me." The syntax of continue statement is simple continue;
b. goto and break
C support goto statement to branch unconditionally from one point to another in the program.The goto keyword is followed by a label, which is basically some identifier placed elsewhere in the program where the control is to be transferred. During running of a program, the statement like “goto label1;” cause the flow of control to the statement immediately following the label “label1”. We can have a forward jump or a backward jump.
#include<studio.h>
void main()
{
int attempt,
number = 46; looping: /* a label */
printf("Guess a number from 0-100\n");
scanf("%d", &attempt); if(number==attempt)
{
printf("You guessed correctly!\n\n");
}
else
{
printf("Let me ask again...\n\n");
goto looping; /* Jump to the label*/
} getch();
}
