Compilare: user.cpp: In function ‘int main()’: user.cpp:25:9: warning: unused variable ‘prod’ [-Wunused-variable] int prod,i,t,nprim,j,x,y; ^ user.cpp:28:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d" ,&t); ^ user.cpp:40:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d%d" ,&x,&y); ^