What is meant by label in c program?

Answer 1

Labels are used in conjunction with goto statements. A goto statement allows us to jump forwards or backwards to a given label:

int x;

again:

printf ("Enter a non-zero number: ");

scanf ("%d\n", &x);

if (x==0)

{

printf ("Input error: number must be non-zero!\n");

goto again;

}

Goto statements should generally be avoided in favour of structured alternatives. The above example would be much better written using a loop:

int x = 0; while (x==0) {

printf ("Enter a non-zero number: ");

scanf ("%d\n", &x);

if (x==0) printf ("Input error: number must be non-zero!\n");

}

Goto statements are ideally suited to jumps out of a nested scope as an alternative to using multiple break statements.

while (true) {

// ...

while (true) {

// ...

if (z==42) goto end; // break out of both loops

}

}

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