c - to input data to structure member is a pointer -

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#include<stdio.h> #include<stdlib.h> struct test {     int x;     int *y; };  main() {     struct test *a;     = malloc(sizeof(struct test));      a->x =10;     a->y = 12;     printf("%d %d", a->x,a->y); }

i o/p there warning

 warning: assignment makes pointer integer without cast

and 

 warning: format ‘%d’ expects type ‘int’, argument 3 has type ‘int *’

how input value *y in struct test

to access, need dereference pointer returned expression a->y maniputlate pointed @ value. this, use unary * operator:

you need allocate memory y make sure points @ something:

a->y = malloc(sizeof(int)); ... *(a->y) = 12; ... printf("%d %d", a->x,*(a->y));

and sure free malloc'd data in reverse order malloc'd

free(a->y); free(a);

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