学步园

前些日子写了个博客，发到论坛里去了，怎么博客里没了？补回来！

原文见http://topic.csdn.net/u/20101028/10/2a6aeda0-2a92-466c-bf35-5aa23f53ad80.html

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import java.text.*;<br /> public class Snake {<br /> private static DecimalFormat df2 = new DecimalFormat("00");<br /> public static void main(String[] args) {<br /> int M = 6;<br /> int N = 6;<br /> boolean firstDown = false;<br /> for(int n=0; n<N; n++){<br /> for(int m=0; m<M; m++){<br /> System.out.print(df2.format(getSnake(m, n, M, N, firstDown)));<br /> System.out.print(" ");<br /> }<br /> System.out.println();<br /> }<br /> }<br /> private static int getSnake(final int m, final int n, final int M, final int N, boolean firstDown){<br /> final int MM = M<N?M:N;<br /> final int NN = M<N?N:M;<br /> final int K = M+N;<br /> final int k = m+n;<br /> int delta;<br /> int max;<br /> if(k<MM){<br /> delta = firstDown?(k%2==0?(n+1):(m+1)):(k%2==0?(m+1):(n+1));<br /> max = k*(k+1)/2;<br /> }else<br /> if(k<NN){<br /> max = MM*(MM-1)/2+(k-MM+1)*MM;<br /> delta = firstDown?(k%2==0?(N>M?M-m:n+1):(N>M?m+1:N-n)):(k%2==0?(N>M?m+1:N-n):(N>M?M-m:n+1));<br /> }else{<br /> max = N*M-(K-k)*(K-k-1)/2;<br /> delta = firstDown?(k%2==0?(M-m):(N-n)):(k%2==0?(N-n):(M-m));<br /> }<br /> return max + delta;<br /> }<br /> }

输出：

01 03 04 10<br /> 02 05 09 11<br /> 06 08 12 18<br /> 07 13 17 19<br /> 14 16 20 23<br /> 15 21 22 24

01 02 06 07<br /> 03 05 08 14<br /> 04 09 13 15<br /> 10 12 16 21<br /> 11 17 20 22<br /> 18 19 23 24<br />

01 03 04 10 11 18<br /> 02 05 09 12 17 19<br /> 06 08 13 16 20 23<br /> 07 14 15 21 22 24<br />

01 02 06 07 14 15<br /> 03 05 08 13 16 21<br /> 04 09 12 17 20 22<br /> 10 11 18 19 23 24

01 02 06 07 15 16<br /> 03 05 08 14 17 26<br /> 04 09 13 18 25 27<br /> 10 12 19 24 28 33<br /> 11 20 23 29 32 34<br /> 21 22 30 31 35 36