I am trying to concatenate a vector of four elements into a 4-byte word to represent as an uint32_t.
Sorry, I don't have my code, but this is what I am trying to do:
vector v; // each element is a byte, with four elements v[0], v[1], v[2], v[3] concatenate these four elements to form a word (I guess a char[32]?) [0][1][2][3] to use as a uint32_t.
I have tried changing v[0,1,2,3] to strings then appending the strings using loops but for whatever reason, the end results was adding erroneous bits.
Thank you so much for the help everyone!
What you are looking for is bit shifting and bitwise OR, eg:
std::vector<uint8_t> v;
// fill v with 4 bytes as needed...
uint32_t i = (uint32_t(v[X1]) << 24) | (uint32_t(v[X2]) << 16) | (uint32_t(v[X3]) << 8) | uint32_t(v[X4]);
Where X1..X4 are the desired byte indexes in the vector, depending on which endian you want to use for the uint32_t.
Alternatively, if the vector elements are already in the correct byte order for the endian you want the uint32_t to be in, you can just memcpy() the bytes as-is:
std::vector<uint8_t> v;
// fill v with 4 bytes as needed...
uint32_t i;
std::memcpy(&i, v.data(), 4);