Compilare: user.c: In function ‘rem’: user.c:88:5: warning: implicit declaration of function ‘malloc’ [-Wimplicit-function-declaration] node* n = malloc(sizeof(node)); ^ user.c:88:15: warning: incompatible implicit declaration of built-in function ‘malloc’ [enabled by default] node* n = malloc(sizeof(node)); ^ user.c: In function ‘paste’: user.c:98:17: warning: incompatible implicit declaration of built-in function ‘malloc’ [enabled by default] node* mix = malloc(sizeof(node)); ^ user.c: In function ‘main’: user.c:152:32: warning: incompatible implicit declaration of built-in function ‘malloc’ [enabled by default] huffman *huff = (huffman*) malloc(MAX_N * sizeof(huffman)); ^