Can you find then flag inside this matrix ?ダウンロードしたファイルを解凍するとflag.txtができます。次のようなテキストデータです。
左上から斜め方向に文字を抽出すると次のような文字列になります。cRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRmRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRFRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRkRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRYRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRXRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRJRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR7RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRYRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR2RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRhRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRhRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRcRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRlRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR9RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRhRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRZRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRnRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRlRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRcRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRlRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR9RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRjRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRaRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRGRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRFRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRyRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRXRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR2RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRdRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRpRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRdRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRmRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRVRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRfRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRZRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRmRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRxRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRhRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRZRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR3RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR0
cmFkYXJ7Y2hhcl9hZnRlcl9jaGFyX2dpdmVfZmxhZ30
これをBASE64でデコードするとフラグになります。
フラグは、
radar{char_after_char_give_flag}