POJ 1013 Counterfeit Dollar 称硬币

12个硬币，有一个假的 或轻或重，找出假硬币

开始用的模拟，考虑很多情况

后来，lmy说轻的-1，重的+1，学数学的看什么都是数字，orz

模拟写的两个差不多的代码：

(一）

#include<iostream>
#include<cstdio>
#include<string>
#include<cstring>
using namespace std;
int vs[15],cnt[15];
int main()
{int CASE,ca,len,i,x,sum;char s1[15],s2[15],s3[8];scanf("%d",&CASE);while(CASE--){sum=0;memset(vs,0,sizeof(vs));memset(cnt,0,sizeof(cnt));for(ca=1;ca<=3;ca++){scanf("%s%s%s",s1,s2,s3);len=strlen(s1);if(s3[0]=='e')//一定是真的{for(i=0;i<len;i++){x=s1[i]-'A';vs[x]=1;x=s2[i]-'A';vs[x]=1;}}if(s3[0]=='u')//前重后轻{sum++;len=strlen(s1);for(i=0;i<len;i++){x=s1[i]-'A';if(!vs[x]){vs[x]=3;cnt[x]=1;}else if(vs[x]==2)vs[x]=1;else if(vs[x]==3)cnt[x]++;x=s2[i]-'A';if(!vs[x]){vs[x]=2;cnt[x]=1;}else if(vs[x]==3)vs[x]=1;else if(vs[x]==2)cnt[x]++;}}if(s3[0]=='d')//前轻后重{sum++;len=strlen(s1);for(i=0;i<len;i++){x=s1[i]-'A';if(!vs[x]){vs[x]=2;cnt[x]++;}else if(vs[x]==3)vs[x]=1;else if(vs[x]==2)cnt[x]++;x=s2[i]-'A';if(!vs[x]){vs[x]=3;cnt[x]++;}else if(vs[x]==2)vs[x]=1;else if(vs[x]==3)cnt[x]++;}}}int mark;for(i=0;i<12;i++){if(vs[i]!=1&&cnt[i]==sum)//vs不能去掉{mark=i;break;}}if(vs[mark]==3)printf("%c is the counterfeit coin and it is heavy.\n",mark+'A');if(vs[mark]==2)printf("%c is the counterfeit coin and it is light.\n",mark+'A');}return 0;
}

　　

　　（二）

#include<iostream>
#include<cstdio>
#include<string>
#include<cstring>
using namespace std;
int vs[15],cnt[15];
int main()
{int CASE,ca,len,i,x,sum;char s1[15],s2[15],s3[8];scanf("%d",&CASE);while(CASE--){sum=0;memset(vs,0,sizeof(vs));memset(cnt,0,sizeof(cnt));for(ca=1;ca<=3;ca++){scanf("%s%s%s",s1,s2,s3);len=strlen(s1);if(s3[0]=='e')//一定是真的{for(i=0;i<len;i++){x=s1[i]-'A';vs[x]=1,cnt[x]=0;//必须写上cnt[x]=0，因为可能第二组或第三组x=s2[i]-'A';vs[x]=1,cnt[x]=0;}}if(s3[0]=='u')//前重后轻{sum++;len=strlen(s1);for(i=0;i<len;i++){x=s1[i]-'A';if(!vs[x]){vs[x]=3;cnt[x]=1;}else if(vs[x]==2){vs[x]=1;cnt[x]=0;}else if(vs[x]==3)cnt[x]++;x=s2[i]-'A';if(!vs[x]){vs[x]=2;cnt[x]=1;}else if(vs[x]==3){vs[x]=1;cnt[x]=0;}else if(vs[x]==2)cnt[x]++;}}if(s3[0]=='d')//前轻后重{sum++;len=strlen(s1);for(i=0;i<len;i++){x=s1[i]-'A';if(!vs[x]){vs[x]=2;cnt[x]++;}else if(vs[x]==3){vs[x]=1;cnt[x]=0;}else if(vs[x]==2)cnt[x]++;x=s2[i]-'A';if(!vs[x]){vs[x]=3;cnt[x]++;}else if(vs[x]==2){vs[x]=1;cnt[x]=0;}else if(vs[x]==3)cnt[x]++;}}}int mark;for(i=0;i<12;i++){if(cnt[i]==sum)//vs[i]!=1去掉了{mark=i;break;}}if(vs[mark]==3)printf("%c is the counterfeit coin and it is heavy.\n",mark+'A');if(vs[mark]==2)printf("%c is the counterfeit coin and it is light.\n",mark+'A');}return 0;
}

　　（三）转成数学加减后的简单代码！！！

#include<iostream>
#include<cstdio>
#include<string>
#include<cstring>
using namespace std;
int cnt[15];
bool vs[15];
int main()
{int CASE,ca,len,i,x,sum;char s1[15],s2[15],s3[8];scanf("%d",&CASE);while(CASE--){sum=0;memset(cnt,0,sizeof(cnt));memset(vs,0,sizeof(vs));for(ca=1;ca<=3;ca++){scanf("%s%s%s",s1,s2,s3);len=strlen(s1);if(s3[0]=='u')//前重后轻{sum++;for(i=0;i<len;i++){x=s1[i]-'A';if(!vs[x])cnt[x]++;}for(i=0;i<len;i++){x=s2[i]-'A';if(!vs[x])cnt[x]--;}}if(s3[0]=='d')//前轻后重{sum++;for(i=0;i<len;i++){x=s1[i]-'A';if(!vs[x])cnt[x]--;}for(i=0;i<len;i++){x=s2[i]-'A';if(!vs[x])cnt[x]++;}}if(s3[0]=='e')//相等{for(i=0;i<len;i++){x=s1[i]-'A';cnt[x]=0;vs[x]=1;}for(i=0;i<len;i++){x=s2[i]-'A';vs[x]=1;cnt[x]=0;}}}int mark;for(i=0;i<12;i++){if(!vs[i])if(cnt[i]==sum||cnt[i]==-sum){mark=i;break;}}if(cnt[mark]>0)printf("%c is the counterfeit coin and it is heavy.\n",mark+'A');if(cnt[mark]<0)printf("%c is the counterfeit coin and it is light.\n",mark+'A');}return 0;
}