exercism/c/grains/grains.c

#include "grains.h"
#include <stdint.h>

uint64_t square(uint8_t index) {

  if (index == 0 || index > MAX_SQUARES) {
    return 0;
  }

  return (uint64_t)1 << (index - 1);
}

uint64_t total(void) {

  uint64_t result = 1;
  for (int i = 1; i <= MAX_SQUARES; i++) {
    result += 1 << i;
  }
  return result;
}