Compilare: main.cpp: In function 'int main()': main.cpp:8:11: warning: variable 'a1' set but not used [-Wunused-but-set-variable] int a,a1,b1,b,cmmdc; ^~ main.cpp:8:14: warning: variable 'b1' set but not used [-Wunused-but-set-variable] int a,a1,b1,b,cmmdc; ^~ main.cpp:9:28: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%i %i",&a,&b); ^