encoded [ i + j ] = ' E ' , ' E ' - ' A ' = 5 ' E ' has 5 th position in char_set .
if ( encoded [ i + j ] . charCodeAt ( 0 ) >= ' ' . charCodeAt ( 0 ) && encoded [ i + j ] . charCodeAt ( 0 ) <= ' ' . charCodeAt ( 0 ) ) num = num | ( encoded [ i + j ] . charCodeAt ( 0 ) - ' ' . charCodeAt ( 0 ) ) ;