Compilare: user.cpp: In function ‘int main()’: user.cpp:59:22: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘long int’ [-Wformat=] fprintf(f2,"%d",r); ^ user.cpp:37:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f1,"%c",&c); ^ user.cpp:43:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f1,"%c",&c); ^