Returns length of LCS for X [ 0. . m - 1 ] , Y [ 0. . n - 1 ] and Z [ 0. . o - 1 ]
static int lcsOf3 ( String X , String Y , String Z , int m , int n , int o ) { int [ ] [ ] [ ] L = new int [ m + 1 ] [ n + 1 ] [ o + 1 ] ;