正态分布:模拟抛硬币

#include <stdio.h>
#include <stdlib.h>

int heads(void)
{ return rand() < RAND_MAX/2; }

int main(int argc, char *argv[])
{
  int i, j, cnt;
  int N = atoi(argv[1]), M = atoi(argv[2]);
  int *f = malloc((N+1)*sizeof(int));

  for (j = 0; j <= N; j++) f[j] = 0;

  for (i = 0; i < M; i++, f[cnt]++)
    for (cnt = 0, j = 0; j <= N; j++)
      if (heads()) cnt++;

  for (j = 0; j <= N; j++)
    {
      printf("%2d ", j);
      for (i = 0; i < f[j]; i+=10) printf("*");
      printf("\n");
    }

  return 0;
}