Description

The game “The Pilots Brothers: following the stripy elephant” has a quest where a player needs to open a refrigerator.

There are 16 handles on the refrigerator door. Every handle can be in one of two states: open or closed. The refrigerator is open only when all handles are open. The handles are represented as a matrix 4х4. You can change the state of a handle in any location [i, j]

The task is to determine the minimum number of handle switching necessary to open the refrigerator.

Input

The input contains four lines. Each of the four lines contains four characters describing the initial state of appropriate handles. A symbol “+” means that the handle is in closed state, whereas the symbol “?” means “open”. At least one of the handles is initially closed.

Output

The first line of the input contains N – the minimum number of switching. The rest N lines describe switching sequence. Each of the lines contains a row number and a column number of the matrix separated by one or more spaces. If there are several solutions, you may give any one of them.

Sample Input

-+--
----
----
-+--

Sample Output

6
1 1
1 3
1 4
4 1
4 3
4 4

Source

 1 #include<iostream>
 2 #include<stdio.h>
 3 using namespace std;
 4 char m[5][5];
 5 int Count[5][5];
 6 //判斷狀態
 7 bool Check()
 8 {
 9     for(int i=1;i<=4;i++)
10         for(int j=1;j<=4;j++)
11         {
12             if(m[i][j] == ‘+‘) return 0;//沒有被全部打開
13         }
14     return 1;
15 }
16 int getAns()
17 {//計算結果
18     int ans = 0;
19     for(int i=1;i<=4;i++)
20     {
21         for(int j=1;j<=4;j++)
22         {
23             if(Count[i][j]%2 == 0)
24             {
25                 Count[i][j] = 0;
26             }else{
27                 Count[i][j] = 1;
28                 ans++;
29             }
30         }
31     }
32     return ans;
33 }
34 int changeState()
35 {
36     for(int i=1;i<=4;i++)
37         for(int j=1;j<=4;j++)
38         {
39             if(m[i][j] == ‘+‘)//開關為關閉狀態
40             {
41                 m[i][j] = ‘-‘;
42                 Count[i][j] += 1;
43                 for(int k = 1;k<=4;k++)
44                 {
45                     if(m[i][k] == ‘+‘) {m[i][k] = ‘-‘;}
46                     else{m[i][k] = ‘+‘;}
47                 }
48                 for(int k=1;k<=4;k++)
49                 {
50                     if(m[k][j] == ‘+‘) {m[k][j] = ‘-‘;}
51                     else{m[k][j] = ‘+‘;}
52                 }
53                 if(Check())
54                 {//進行結果輸出
55                     return getAns();
56                 }
57             }
58         }
59         if(Check() == 0) return changeState();
60 }
61 
62 int main()
63 {
64     char c;
65     //初始化
66     while(true)
67     {
68         for(int i = 1;i<=4;i++)
69             for(int j=1;j<=4;j++)
70                 Count[i][j] = 0;
71         for(int i=1;i<=4;i++)
72         {
73             for(int j=1;j<=4;j++)
74             {
75                 if((c = getchar()) == EOF) return 0;
76                 m[i][j] = c;
77             }
78             c = getchar();
79         }
80 
81         cout<<changeState()<<endl;
82         for(int i=1;i<=4;i++)
83         {
84             for(int j=1;j<=4;j++)
85             {
86                 if(Count[i][j] == 1) cout<<i<<" "<<j<<endl;
87             }
88         }
89     }
90 
91     return 0;
92 }

 1 #include<iostream>
 2 #include<stdio.h>
 3 #include<string.h>
 4 using namespace std;
 5 char m[5][5];
 6 int Count[5][5];
 7 //判斷狀態
 8 bool Check()
 9 {
10     for(int i=1;i<=4;i++)
11         for(int j=1;j<=4;j++)
12         {
13             if(m[i][j] == ‘+‘) return 0;//沒有被全部打開
14         }
15     return 1;
16 }
17 int getAns()
18 {//計算結果
19     int ans = 0;
20     for(int i=1;i<=4;i++)
21     {
22         for(int j=1;j<=4;j++)
23         {
24             if(Count[i][j]%2 == 0)
25             {
26                 Count[i][j] = 0;
27             }else{
28                 Count[i][j] = 1;
29                 ans++;
30             }
31         }
32     }
33     return ans;
34 }
35 int main()
36 {
37     char c;
38     while(true)
39     {
40         memset(Count,0,sizeof(Count));//初始化
41         for(int i=1;i<=4;i++)
42         {
43             for(int j=1;j<=4;j++)
44             {
45                 if((c = getchar()) == EOF) return 0;
46                 m[i][j] = c;
47                 if(c == ‘+‘)
48                 {
49                     for(int k=1;k<=4;k++)
50                     {
51                         Count[k][j]++;
52                         Count[i][k]++;
53                     }
54                     Count[i][j]--;
55                 }
56             }
57             c = getchar();
58         }
59         ///打印結果
60         cout<<getAns()<<endl;
61         for(int i=1;i<=4;i++)
62         {
63             for(int j=1;j<=4;j++)
64             {
65                 if(Count[i][j] == 1) cout<<i<<" "<<j<<endl;
66             }
67         }
68     }
69 
70     return 0;
71 }

2965 -- The Pilots Brothers' refrigerator