北大poj 1013 Counterfeit Dollar 一种解法

http://acm.pku.edu.cn/JudgeOnline/problem?id=1013

参考了http://www.skywind.name/blog/?p=143

顺便介绍一个网站 http://www.curiouser.co.uk/frames/creframe.html?http://www.curiouser.co.uk/puzzles/12bsolutions.htm, 里面有12balls问题的各种奇怪解法. 

 开始一直WA, 原来是light和heavy后面没有加句号"."!!!!

 

 1#include <iostream>
 2#include <string>
 3#include <fstream>
 4#include <memory.h>
 5using namespace std;
 6
 7int main()
 8{
 9    int c[12][3];
10    int res[3];
11    int n, i, j;
12
13    cin>>n;
14    while(n--) {
15        memset(c, 0, sizeof(c));
16        memset(res, 0, sizeof(res));
17        string s1, s2, s3;
18        for(i=0; i<3; i++){
19            cin>>s1>>s2>>s3;
20            for(j=0; j<s1.size(); j++) {
21                c[s1[j]-'A'][i] = 1;
22                c[s2[j]-'A'][i] = -1;
23            }
24            if(s3=="even"){
25                res[i] = 0;
26            }
27            else if(s3=="up"){
28                res[i] = 1;
29            }
30            else {
31                res[i] = -1;
32            }
33        }
34        for(i=0; i<13; i++) {
35            if(c[i][0]==res[0] && c[i][1]==res[1] && c[i][2]==res[2]) {
36                cout<<char('A'+i)<<" is the counterfeit coin and it is heavy."<<endl;;
37                break;
38            }
39            else if(c[i][0]==-res[0] && c[i][1]==-res[1] && c[i][2]==-res[2]) {
40                cout<<char('A'+i)<<" is the counterfeit coin and it is light."<<endl;;
41                break;
42            }
43        }
44    }
45    return 0;
46}

 

下面是枚举的方法:

 1int main()
 2{
 3    int c[12];
 4    int res[3];
 5    int n, i, j;
 6    cin>>n;
 7    while(n--) {
 8        memset(c, 0, sizeof(c));
 9        memset(res, 0, sizeof(res));
10        string s1[3], s2[3], s3[3];
11        for(i=0; i<3; i++){
12            cin>>s1[i]>>s2[i]>>s3[i];
13        }
14        for(i=0; i<12; i++) {
15            memset(c, 0, sizeof(c));
16            c[i] = 1;
17            int left, right;
18            for(j=0; j<3; j++) {
19                left = 0; right = 0;
20                for(int k=0; k<s1[j].size(); k++) {
21                    left  += c[s1[j][k]-'A'];
22                    right += c[s2[j][k]-'A'];
23                }
24                if( (left>right && s3[j]!="up") || (left<right && s3[j]!="down") 
25                    || (left==right && s3[j]!="even") ){
26                    break;
27                }
28            }
29            if(j==3) {
30                cout<<char('A'+i)<<" is the counterfeit coin and it is heavy."<<endl;
31            }
32            c[i] = -1;
33            for(j=0; j<3; j++) {
34                left = 0; right = 0;
35                for(int k=0; k<s1[j].size(); k++) {
36                    left  += c[s1[j][k]-'A'];
37                    right += c[s2[j][k]-'A'];
38                }
39                if( (left>right && s3[j]!="up") || (left<right && s3[j]!="down") 
40                    || (left==right && s3[j]!="even") ){
41                    break;
42                }
43            }
44            if(j==3) {
45                cout<<char('A'+i)<<" is the counterfeit coin and it is light."<<endl;
46            }
47        }
48    }
49    return 0;
50}

 

 

 

 

 1#include <iostream>
 2#include <string>
 3#include <fstream>
 4#include <memory.h>
 5using namespace std;
 6
 7int main()
 8{
 9    int c[12][3];
10    int res[3];
11    int n, i, j;
12
13    cin>>n;
14    while(n--) {
15        memset(c, 0, sizeof(c));
16        memset(res, 0, sizeof(res));
17        string s1, s2, s3;
18        for(i=0; i<3; i++){
19            cin>>s1>>s2>>s3;
20            for(j=0; j<s1.size(); j++) {
21                c[s1[j]-'A'][i] = 1;
22                c[s2[j]-'A'][i] = -1;
23            }
24            if(s3=="even"){
25                res[i] = 0;
26            }
27            else if(s3=="up"){
28                res[i] = 1;
29            }
30            else {
31                res[i] = -1;
32            }
33        }
34        for(i=0; i<13; i++) {
35            if(c[i][0]==res[0] && c[i][1]==res[1] && c[i][2]==res[2]) {
36                cout<<char('A'+i)<<" is the counterfeit coin and it is heavy."<<endl;;
37                break;
38            }
39            else if(c[i][0]==-res[0] && c[i][1]==-res[1] && c[i][2]==-res[2]) {
40                cout<<char('A'+i)<<" is the counterfeit coin and it is light."<<endl;;
41                break;
42            }
43        }
44    }
45    return 0;
46}