Following steps build L [ m + 1 ] [ n + 1 ] [ o + 1 ] in bottom up fashion . Note that L [ i ] [ j ] [ k ] contains length of LCS of X [ 0. . i - 1 ] and Y [ 0. . j - 1 ] and Z [ 0. . ... k - 1 ]
for i in range ( m + 1 ) : NEW_LINE INDENT for j in range ( n + 1 ) : NEW_LINE INDENT for k in range ( o + 1 ) : NEW_LINE INDENT if ( i == 0 or j == 0 or k == 0 ) : NEW_LINE INDENT L [ i ] [ j ] [ k ] = 0 NEW_LINE DEDENT elif ( X [ i - 1 ] == Y [ j - 1 ] and X [ i - 1 ] == Z [ k - 1 ] ) : NEW_LINE INDENT L [ i ] [ j ] [ k ] = L [ i - 1 ] [ j - 1 ] [ k - 1 ] + 1 NEW_LINE DEDENT else : NEW_LINE INDENT L [ i ] [ j ] [ k ] = max ( max ( L [ i - 1 ] [ j ] [ k ] , L [ i ] [ j - 1 ] [ k ] ) , L [ i ] [ j ] [ k - 1 ] ) NEW_LINE DEDENT DEDENT DEDENT DEDENT