Created
December 4, 2012 19:18
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import java.util.*; | |
public class Solution{ | |
public final static int MAX_NUMBER_OF_STATES = 390625;//5^8 | |
class State{ | |
int steps; | |
int[] conf; | |
int peg1, peg2; | |
int prev; | |
State(int steps, int[] conf, int peg1, int peg2, int prev){ | |
this.steps = steps; | |
this.conf = conf.clone(); | |
this.peg1 = peg1; | |
this.peg2 = peg2; | |
this.prev = prev; | |
} | |
} | |
Comparator<int[]> cmp; | |
State[] queue; | |
int nQ, sol; | |
int N, K; | |
int[] initial, target; | |
void read(){ | |
Scanner in = new Scanner(System.in); | |
N = in.nextInt(); | |
K = in.nextInt(); | |
initial = new int[K+1]; | |
target = new int[K+1]; | |
for(int i=1; i<=N;++i){ | |
int x = in.nextInt(); | |
initial[x] |= (1<<i); | |
} | |
for(int i=1; i<=N;++i){ | |
int x = in.nextInt(); | |
target[x] |= (1<<i); | |
} | |
in.close(); | |
} | |
int getFirstBit(int conf){ | |
for(int bit=1; bit <= N; ++bit) | |
if((conf & (1<<bit)) > 0) | |
return bit; | |
return 0; | |
} | |
void solve(){ | |
queue = new State[MAX_NUMBER_OF_STATES]; | |
cmp = new Comparator<int[]>(){ | |
@Override | |
public int compare(int[] arg0, int[] arg1) { | |
for(int i=0; i<arg0.length; ++i) | |
if(arg0[i] != arg1[i]) | |
return arg0[i] - arg1[i]; | |
return 0; | |
}}; | |
Set<int[]> used = new TreeSet<int[]>(cmp); | |
queue[nQ = 0] = new State(0, initial, 0, 0, -1); | |
used.add(initial); | |
int conf[] = new int[K+1]; | |
for(int p=0; p<=nQ; ++p){ | |
if(cmp.compare(queue[p].conf, target) == 0){ | |
sol = p; | |
return; | |
} | |
for(int i=1; i<=K; ++i) | |
for(int j=1; j<=K; ++j){ | |
conf = queue[p].conf.clone(); | |
int disk1 = getFirstBit(conf[i]); | |
int disk2 = getFirstBit(conf[j]); | |
if(disk1 == 0 || (disk1 > disk2 && disk2 != 0) || i == j) | |
continue; | |
conf[i] -= (1<<disk1); | |
conf[j] |= (1<<disk1); | |
if(used.contains(conf)) | |
continue; | |
queue[++nQ] = new State(queue[p].steps + 1, conf, i, j, p); | |
used.add(conf); | |
} | |
} | |
} | |
void print(int i){ | |
if(i == 0) | |
return; | |
print(queue[i].prev); | |
System.out.println(queue[i].peg1 + " " + queue[i].peg2); | |
} | |
Solution(){ | |
read(); | |
solve(); | |
System.out.println(queue[sol].steps); | |
print(sol); | |
} | |
public static void main(String[] args){ | |
new Solution(); | |
} | |
} |
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