prog.c: In function 'main':
prog.c:16:17: error: format '%d' expects a matching 'int' argument [-Werror=format=]
printf("%1d%1d%1d",b,a);
^
prog.c:19:11: error: format '%d' expects a matching 'int' argument [-Werror=format=]
printf("%1d,a");
^
cc1: all warnings being treated as errors