Compilare: user.cpp:2:6: warning: ISO C++ forbids declaration of ‘main’ with no type [-Wreturn-type] main(){FILE*f=fopen("adunare.in","r"),*g=fopen("adunare.out","w");int a,b;fscanf(f,"%d%d",&a,&b);fprintf(g,"%d",a+b);} ^ user.cpp: In function ‘int main()’: user.cpp:2:97: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] main(){FILE*f=fopen("adunare.in","r"),*g=fopen("adunare.out","w");int a,b;fscanf(f,"%d%d",&a,&b);fprintf(g,"%d",a+b);} ^