Way to search for a "subarray" within an array?

Sorry for how nooby this sounds. What is the most efficient way to search for another array within an array? For example say I want to search for {5,6,7} within {1,2,3,4,5,6,7}. Thanks

Look the first digit of "subarray" in a big array, if it match - test next digits one by one

The Searching functions of the string.h header file are how to accomplish what @b707 said.
See https://cplusplus.com/reference/cstring/ With them you can search arrays and strings,

Iterating over the larger array and using memcmp() would do. Stop when there is a match or not enough elements left in the larger array then it’s no match