Create 1429.pas

QUSTOJ/1429.pas

@@ -0,0 +1,33 @@
+const
+  step:integer=0;
+  chars:array[0..15] of char=('0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F');
+var
+  digit:array[char] of integer;
+  i,n,g:integer;
+  m,s:string;
+  ok:boolean;
+begin
+  for i:=0 to 9 do digit[char(ord('0')+i)]:=i;
+  for i:=0 to 5 do digit[char(ord('A')+i)]:=i+10;
+ readln(n);
+readln(s);
+  for i:=1 to length(s) do s[i]:=upcase(s[i]);
+  repeat
+    ok:=true;
+    for i:=1 to length(s) div 2 do
+      if s[i]<>s[length(s)+1-i] then ok:=false;
+    if ok then break;
+    inc(step);
+    m:=s; g:=0;
+    for i:=length(m) downto 1 do
+    begin
+      s[i]:=chars[(digit[m[i]]+digit[m[length(m)+1-i]]+g) mod n];
+      g:=(digit[m[i]]+digit[m[length(m)+1-i]]+g) div n;
+    end;
+    if g>0 then s:=chars[g]+s;
+  until step>=30;
+  if ok then
+    writeln('STEP=',step)
+  else
+    writeln('Impossible');
+end.