操作间没有次序关系，同一个操作最多重复3次。。。
可以直接暴力。。。
IOI'94 - Day 2
|-------| |-------| |-------|
| | | | | | |
|---O | |---O | | O |
| | | | | |
|-------| |-------| |-------|
A B C
|-------| |-------| |-------|
| | | | | |
| O | | O | | O |
| | | | | | | | |
|-------| |-------| |-------|
D E F
|-------| |-------| |-------|
| | | | | |
| O | | O---| | O |
| | | | | | | |
|-------| |-------| |-------|
G H I
The goal is to find a minimal sequence of moves to return all the dials to 12 o'clock. Nine different ways to turn the dials on the clocks are supplied via a table below; each way is called a move. Select for each move a number 1 through 9 which will cause the dials of the affected clocks (see next table) to be turned 90 degrees clockwise.
| Move | Affected clocks |
| 1 | ABDE |
| 2 | ABC |
| 3 | BCEF |
| 4 | ADG |
| 5 | BDEFH |
| 6 | CFI |
| 7 | DEGH |
| 8 | GHI |
| 9 | EFHI |
Example
Each number represents a time according to following table:9 9 12 9 12 12 9 12 12 12 12 12 12 12 12 6 6 6 5 -> 9 9 9 8-> 9 9 9 4 -> 12 9 9 9-> 12 12 12 6 3 6 6 6 6 9 9 9 12 9 9 12 12 12
[But this might or might not be the `correct' answer; see below.]
PROGRAM NAME: clocks
INPUT FORMAT
| Lines 1-3: | Three lines of three space-separated numbers; each number represents the start time of one clock, 3, 6, 9, or 12. The ordering of the numbers corresponds to the first example above. |
SAMPLE INPUT (file clocks.in)
9 9 12 6 6 6 6 3 6
OUTPUT FORMAT
A single line that contains a space separated list of the shortest sequence of moves (designated by numbers) which returns all the clocks to 12:00. If there is more than one solution, print the one which gives the lowest number when the moves are concatenated (e.g., 5 2 4 6 < 9 3 1 1).
SAMPLE OUTPUT (file clocks.out)
4 5 8 9
/*
ID:qhn9992
PROG:clocks
LANG:C++11
*/
#include
#include
#include
#include
using namespace std; int a[10],c[10]; int b[10][10] ={ 0,0,0,0,0,0,0,0,0,0, 1,1,0,1,1,0,0,0,0,0, 1,1,1,0,0,0,0,0,0,0, 0,1,1,0,1,1,0,0,0,0, 1,0,0,1,0,0,1,0,0,0, 0,1,0,1,1,1,0,1,0,0, 0,0,1,0,0,1,0,0,1,0, 0,0,0,1,1,0,1,1,0,0, 0,0,0,0,0,0,1,1,1,0, 0,0,0,0,1,1,0,1,1,0 }; int main() { freopen("clocks.in","r",stdin); freopen("clocks.out","w",stdout); int cnt=0; for(int i=1;i<=9;i++) { scanf("%d",a+i); a[i]=(a[i]/3)%4; } for(c[1]=0;c[1]<4;c[1]++) { for(c[2]=0;c[2]<4;c[2]++) { for(c[3]=0;c[3]<4;c[3]++) { for(c[4]=0;c[4]<4;c[4]++) { for(c[5]=0;c[5]<4;c[5]++) { for(c[6]=0;c[6]<4;c[6]++) { for(c[7]=0;c[7]<4;c[7]++) { for(c[8]=0;c[8]<4;c[8]++) { for(c[9]=0;c[9]<4;c[9]++) { ///check.... bool flag=true; for(int i=1;i<=9;i++) { int t=a[i]; for(int j=1;j<=9;j++) { t+=b[j][i-1]*c[j]; } t=t%4; if(t) { flag=false; break; } } if(flag) { for(int i=1;i<=9;i++) { while(c[i]--) { if(flag) { flag=false; } else putchar(32); printf("%d",i); } } putchar(10); return 0; } else continue; } } } } } } } } } return 0; }