import std.stdio;char x;int y,z=20;int[1700]a;void main(){scanf("%c%d ",&x,&y)<0?z%20*!a[z]&&a[z-1]+a[z+1]+a[z-20]+a[z+20]&&writeln(x=z/20+z/1460,z%20),++z:++a[z*(x-x/73)+y];main;}
Note that non-ascii characters in the above source code will be escaped (such as \x9f).