12个硬币称三次c语言,十二硬币的C语言判别

十二硬币判别代码

人间客制作

国外流行的12个硬币问题：12硬币中可能有一个假的，而且不知道假币比真币重还是轻，给你一架天平，天平没有示数，只能判断是平衡还是不平，且只准称三次，让你判断是否有假币；如果有，找出来。解法思想如下：

第一步：任选8个比较，如选：⑴⑵⑶⑷ 比 ⑸⑹⑺⑻

一、若一样重，则假币在⑼～⑿中，第二步：⑼⑽ 比⑾⑴

1.若一样重，则可能的假币为⑿。则第三步：⑴ vs ⑿

1)若一样重，则没有假币；

2)不一样重，则假币为⑿：如果(1)>(12)，则假币轻，反之，假币重；

2.若⑼⑽重，则第三步：⑼ 比 ⑽

1)若一样重，则假币为⑾(较轻)

2)不一样重，则假币为⑼、⑽中较重者

3.若⑼⑽轻，则第三步：⑼ 比 ⑽

1)若一样重，则假币为⑾(较重)

2)不一样重，则假币为⑼、⑽中较轻者

二、若⑴⑵⑶⑷重，则第二步：⑴⑵⑸ 比 ⑶⑷⑹

1.若一样重，则假币在⑺⑻中，第三步：⑺ 比 ⑻

假币为⑺、⑻中较轻者

2.若⑴⑵⑸端较重，则假币在⑴⑵⑹中，第三步：⑴比 ⑵

1)若一样重，则假币为⑹(较轻)

2)不一样重，则假币为⑴⑵中较重者

3.若⑶⑷⑹端较重，则假币在⑶⑷⑸中，第三步：⑶ 比 ⑷

1)若一样重，则假币为⑸(较轻)

2)不一样重，则假币为⑶、⑷中较重者

三、若⑴⑵⑶⑷轻，则与上面类似，第二步：⑴⑵⑸比 ⑶⑷⑹

1.若一样重，则假币在⑺⑻中，第三步：⑺ 比 ⑻

假币为⑺、⑻中较重者

2.若⑴⑵⑸端较轻，则假币在⑴⑵⑹中，第三步：⑴ 比 ⑵

1)若一样重，则假币为⑹(较重)

2)不一样重，则假币为⑴⑵中较轻者

3.若⑶⑷⑹端较轻，则假币在⑶⑷⑸中，第三步：⑶ 比 ⑷

1)若一样重，则假币为⑸(较重)

2)不一样重，则假币为⑶、⑷中较轻者

在科技发达的时代，我们都不愿意去做这样繁琐的比较，而是想借助于计算机的威力，下面给大家介绍一种方法，可以在很短的时间内完成中比较。当然，这类问题转化到编程上去后，主要考查的是大家的编程思想，而不再是12硬币问题本身了，因为12个硬币的重量需要大家自己去输入，这些数据只是为了检验大家程序的正确与否。下面是该问题的代码：

#include void main()

{

int i;

float a[12];

for(i=0;i<12;i++)

scanf("%f",&a[i]);

if(a[0]+a[1]+a[2]+a[3]==a[4]+a[5]+a[6]+a[7])

{

if(a[0]+a[1]+a[2]==a[8]+a[9]+a[10])

{

if(a[8]==a[11])

printf("There is no special coin!\n");

else if(a[8]>a[11])

printf("There is a special coin:%f(12) and its lighter than others.\n",a[11]);

else

printf("There is a special coin:%f(12) and its heavier than others.\n",a[11]);

}

else if(a[0]+a[1]+a[2]>a[8]+a[9]+a[10])

{

if(a[8]==a[9])

printf("There is a special coin:%f(11) and its lighter than others.\n",a[10]);

else if(a[8]>a[9])

printf("There is a special coin:%f(10) and its lighter than others.\n",a[9]);

else

printf("There is a special coin:%f(9) and its lighter than others.\n",a[8]);

}

else

{

if(a[8]==a[9])

printf("There is a special coin:%f(11) and its heavier than others.\n",a[10]);

else if(a[8]>a[9])

printf("There is a special coin:%f(9) and its heavier than others.\n",a[8]);

else

printf("There is a special coin:%f(10) and its heavier than others.\n",a[9]);

}

}

else if(a[0]+a[1]+a[2]+a[3]>a[4]+a[5]+a[6]+a[7])

{

if(a[0]+a[2]+a[5]==a[1]+a[4]+a[8])

{

if(a[6]==a[7])

printf("There is a special coin:%f(4) and its heavier than others.\n",a[3]);

else if(a[6]>a[7])

printf("There is a special coin:%f(8) and its lighter than others.\n",a[7]);

else

printf("There is a special coin:%f(7) and its lighter than others.\n",a[6]);

}

else if(a[0]+a[2]+a[5]>a[1]+a[4]+a[8])

{

if(a[0]==a[2])

printf("There is a special coin:%f(5) and its lighter than others.\n",a[4]);

else if(a[0]>a[2])

printf("There is a special coin:%f(1) and its heavier than others.\n",a[0]);

else

printf("There is a special coin:%f(3) and its heavier than others.\n",a[2]);

}

else

{

if(a[1]>a[8])

printf("There is a special coin:%f(2) and its heavier than others.\n",a[1]);

if(a[5]a[7])

printf("There is a special coin:%f(7) and its heavier than others.\n",a[6]);

else

printf("There is a special coin:%f(8) and its heavier than others.\n",a[7]);

}

else if(a[0]+a[2]+a[5]a[2])

printf("There is a special coin:%f(3) and its lighter than others.\n",a[2]);

else

printf("There is a special coin:%f(1) and its lighter than others.\n",a[0]);

}

else

{

if(a[1]a[8])

printf("There is a special coin:%f(6) and its heavier than others.\n",a[5]);

}

}

}

部分结果的截图：