Main.cc: In function 'int main()': Main.cc:7:33: error: 'print' was not declared in this scope print("%d%d%d%d%d",e,d,c,b,a); ^ Main.cc:6:44: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%1d%1d%1d%1d%1d",&a,&b,&c,&d,&e); ^