Do not count last null character .
len_str -= 1 ; Console . Write ( " Encoded ▁ String ▁ : ▁ { 0 } STRNEWLINE " , String . Join ( " " , encoded_String ) ) ; Console . Write ( " Decoded _ String ▁ : ▁ { 0 } STRNEWLINE " , base64Decoder ( encoded_String , len_str ) ) ; } }