数学模型中包括多个变量的例子：称硬币

//数学模型中包括多个变量的例子：称硬币
#include<stdio.h>
#include<string.h>

char left[3][7],right[3][7],result[3][7];
bool isHeavy(char);
bool isLight(char);

int main()
{
	int n;
	char c;
	scanf("%d",&n);
	while(n>0)
	{
		for(int i=0;i<3;i++)
			scanf("%s%s%s",left[i],right[i],result[i]);
		for(c='A';c<='L';c++)
		{
			if(isLight(c))
			{
				printf("%c is the counterfeit coin and it is light.\n",c);
				break;
			}				
			if(isHeavy(c))
			{
				printf("%c is the counterfeit coin and it is heavy.\n",c);
				break;
			}				
		}
		n--;
	}
	return 0;
}
bool isLight(char x)
{
	int i;
	for(i=0;i<3;i++)
	{
		switch(result[i][0])
		{
			case 'u':if(strchr(right[i],x)==NULL) return false;
			break;
			case 'e':if(strchr(right[i],x)!=NULL||strchr(left[i],x)!=NULL) return false;
			break;
			case 'd':if(strchr(left[i],x)==NULL) return false;
			break;
		}
	}
	return true;
}
bool isHeavy(char c)
{
	int i;
	for(i=0;i<3;i++)
	{
		switch(result[i][0])
		{
			case 'u':if(strchr(left[i],c)==NULL) return false;
			break;
			case 'e':if(strchr(left[i],c)!=NULL||strchr(right[i],c)!=NULL) return false;
			break;
			case 'd':if(strchr(right[i],c)==NULL) return false;
			break;
		}
	}
	return true;
}