How to perform split and join functions on Array in C? -

how can perform join , split functions on array elements in c?

for example, let's have 2 arrays:

int value[]=  {0,1,2,3}; int id[]  = {1,1,3,3}; // want join elements of "value" array whoz value of "id" same. //in case 0,1 elements "value" array has same "id" value 1,1 //and 2,3 "value" has same "id" value 3,3. join {01,23} //and if want perform split function give me back{0,1,2,3} 

i did same thing in perl script not sure how can functionality in c?

c doesn't have built-in "dynamic" arrays of many higher-level languages.

you must allocate needed storage using malloc(), copy desired data element element new array.

also can't quite understand desired operations describe ... "join elements of value value of id same" doesn't make sense.

do want compute intersection of arrays? they're not sets, doesn't sound right either.