Convert Unicode code points to UTF-8 and UTF-32

Question

I can\'t think of a way to remove the leading zeros. My goal was in a for loop to then create the UTF-8 and UTF-32 versions of each number.

For example,

Answer 1

Many ways to do this fun exercise, converting a code point to UTF-8.

As not to give it all the coding experience away, following is a pseudo code to get OP started.

#define UTF_WIDTH1_MAX       0x7F
#define UTF_WIDTH2_MAX       0x7FF
#define UTF_WIDTH3_MAX       0xFFFF
#define UTF_WIDTH4_MAX       0x10FFFF

void PrintCodepointUTF8(uint32_t codepoint) {
  uint8_t first;
  uint8_t continuation_bytes[3];
  unsigned continuation_bytes_n;
  if (codepoint <= UTF_WIDTH1_MAX) {
    first = codepoint;
    continuation_bytes = 0;
  } else if (codepoint <= UTF_WIDTH2_MAX) {
    // extract 5 bits for first and 6 bits for one continuation_byte
    // and set some bits
    first = ...;
    continuation_bytes = ...
    continuation_bytes_n = 1;
  } else   if (codepoint <= UTF_WIDTH4_MAX) {
    if (isasurrogate(codepoint)) fail.
    // else extract 4 bits for first and 6 bits for each continuation_byte
    // and set some bits
    first = ...;
    continuation_bytes = ...
    continuation_bytes_n = 2;
  } else   if (codepoint <= UTF_WIDTH4_MAX) {
    // extract 3 bits for first and 6 bits for each continuation_byte
    // and set some bits
    first = ...;
    continuation_bytes = ...
    continuation_bytes_n = 3;
  } else {
    fail out of range.
  }
  print first and 0-3 continuation_bytes
}