diff options
Diffstat (limited to 'others/volume1/061.pas')
-rw-r--r-- | others/volume1/061.pas | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/others/volume1/061.pas b/others/volume1/061.pas new file mode 100644 index 0000000..46bf839 --- /dev/null +++ b/others/volume1/061.pas @@ -0,0 +1,21 @@ +var + n, i: int16; + a, b: array of int16; + +begin + readln(n); + setlength(a, n); + setlength(b, n); + for i := 0 to n - 1 do + begin + read(a[i]); + b[a[i] - 1] := i + 1 + end; + for i := 0 to n - 1 do + if a[i] <> b[i] then + begin + writeln('NO'); + exit + end; + writeln('YES') +end. |