Compilare: user.c: In function ‘pollBeginning’: user.c:57:5: warning: implicit declaration of function ‘isEmpty’ [-Wimplicit-function-declaration] if(!isEmpty(deque)) { ^ user.c:71:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.c: In function ‘pollEnd’: user.c:86:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.c: In function ‘getLastElement’: user.c:92:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.c: In function ‘getFirstElement’: user.c:98:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.c: In function ‘main’: user.c:125:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d %d",&N,&K); ^ user.c:129:15: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d",&A[i]); ^