Function remove_substr_str

leif.c:1451–1456

}

void remove_substr_str(char *str, int start_index, int end_index) {
  int len = strlen(str);

  memmove(str + start_index, str + end_index + 1, len - end_index);
  str[len - (end_index - start_index) + 1] = '\0'; 
}

void insert_i_str(char *str, char ch, int32_t index) {
  int len = strlen(str);