有A、B、C、D、E五人，每人额头上都帖了一张黑或白的纸。五人对坐，每人都可以看到其它人额头上的纸的颜色。五人相互观察后，
    A说：“我看见有三人额头上帖的是白纸，一人额头上帖的是黑纸。”
    B说：“我看见其它四人额头上帖的都是黑纸。”
    C说：“我看见一人额头上帖的是白纸，其它三人额头上帖的是黑纸。”
    D说：“我看见四人额头上帖的都是白纸。”
    E什么也没说。
    现在已知额头上帖黑纸的人说的都是谎话，额头帖白纸的人说的都是实话。问这五人谁的额头是帖白纸，谁的额头是帖黑纸？

Dev-C++:

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

int main(int argc, char *argv[])
{
        int a,b,c,d,e;
    for(a=0;a<=1;a++)           
        for(b=0;b<=1;b++)       
            for(c=0;c<=1;c++)
                for(d=0;d<=1;d++)
                    for(e=0;e<=1;e++)
                        if((a&&b+c+d+e==3||!a&&b+c+d+e!=3)
                            &&(b&&a+c+d+e==0||!b&&a+c+d+e!=0)
                            &&(c&&a+b+d+e==1||!c&&a+b+d+e!=1)
                            &&(d&&a+b+c+e==4||!d&&a+b+c+e!=4))
                        {
                            printf("A is pasted a piece of %s paper on his forehead.\n",
                                                            a?"white":"black");
                            printf("B is pasted a piece of %s paper on his forehead.\n",
                                                            b?"white":"black");
                            printf("C is pasted a piece of %s paper on his forehead.\n",
                                                            c?"white":"black");
                            printf("D is pasted a piece of %s paper on his forehead.\n",
                                                            d?"white":"black");
                            printf("E is pasted a piece of %s paper on his forehead.\n",
                                                            e?"white":"black");
                       }
  system("PAUSE"); 
  return 0;
}