mock.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>
#include <ctype.h>

int main(void) {
  srand(time(0));
  char asd[10000];
  fgets(asd, 10000, stdin);
  const size_t len = strlen(asd);
  for(int i = 0; i < len; i++)
  {
    asd[i] = tolower(asd[i]);
  }
  for(int i = 0; i < 10000; i++)
  {
    int random = rand() % 3;
    if(random + i < 10000)
    {
      asd[i + random] = toupper(asd[i+random]);
    }
    else
    {
      break;
    }
  }
  puts(asd);
  return 0;
}