斐波那契堆栈实现（递归的代码实现）
之前的写法比较屌丝，从同事那来个比较高大上的，让脑袋转转
package ext.pack.test;
import java.util.Stack;
public class HelloWorld extends TestInterface {
public static void printStack(Stack stack) {
System.out.println("STACK:BEGIN");
int STACK_SIZE = stack.size();
for (int i = STACK_SIZE; i > 0; i--) {
T[] objs = stack.get(i - 1);
for (T obj : objs) {
System.out.print(obj + ",");
}
System.out.println();
}
System.out.println("STACK:END");
}
public static void c2(int n) {
long s = 0, rt = 0;
int branch = 0;
Stack stack = new Stack();
while (true) {
if (n < 2) {
// this will goto last one, as nothing to operate
// pop next things to operate, define $rt as last result in {0,1}
// we have the result, there is no need for current stack.
rt = n;
System.out.println("Print $$n<2, n="+n);
} else {
switch (branch) {
case 0: {
do {
stack.push(new Object[] { branch, 0l, n });
n -= 2;
} while (n >= 2);
System.out.print("branch=0,");
printStack(stack);
System.out.println("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$");
continue;
}
case 1: {
// push the F(n-1)
stack.push(new Object[] { branch, rt, n });
// process F(n-2), goto $BRANCH=0
n--;
branch = 0;
System.out.print("branch=1,");
printStack(stack);
System.out.println("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$");
continue;
}
case 2: {
// calc rs til now in one F(n),calc from $BRANCH=1, $BRANCH++
// we have the result, there is no need for current stack.
System.out.println("We have the previous Result!!");
rt += s;
break;
}
default:
break;
}
}
if (stack.isEmpty()) {
System.out.println("Result is :" + rt);
return;
}
Object[] t = stack.pop();
branch = (Integer) t[0];
s = (Long) t[1];
n = (Integer) t[2];
System.out.println("POPUP Branch=" + branch + " s=" + s + " n=" + n + " rt=" + rt);
printStack(stack);
System.out.println("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$");
branch++;
}
}
public static void main(String[] args) {
c2(6);
}
}
Log分析：
branch=0,STACK:BEGIN
0,0,2,
0,0,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=0
POPUP Branch=0 s=0 n=2 rt=0
STACK:BEGIN
0,0,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,0,2,
0,0,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=1
POPUP Branch=1 s=0 n=2 rt=1
STACK:BEGIN
0,0,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=0 s=0 n=4 rt=1
STACK:BEGIN
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,1,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=0,STACK:BEGIN
0,0,3,
1,1,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=1
POPUP Branch=0 s=0 n=3 rt=1
STACK:BEGIN
1,1,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,1,3,
1,1,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=0,STACK:BEGIN
0,0,2,
1,1,3,
1,1,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=0
POPUP Branch=0 s=0 n=2 rt=0
STACK:BEGIN
1,1,3,
1,1,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,0,2,
1,1,3,
1,1,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=1
POPUP Branch=1 s=0 n=2 rt=1
STACK:BEGIN
1,1,3,
1,1,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=1 s=1 n=3 rt=1
STACK:BEGIN
1,1,4,
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=1 s=1 n=4 rt=2
STACK:BEGIN
0,0,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=0 s=0 n=6 rt=3
STACK:BEGIN
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=0,STACK:BEGIN
0,0,3,
0,0,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=1
POPUP Branch=0 s=0 n=3 rt=1
STACK:BEGIN
0,0,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,1,3,
0,0,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=0,STACK:BEGIN
0,0,2,
1,1,3,
0,0,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=0
POPUP Branch=0 s=0 n=2 rt=0
STACK:BEGIN
1,1,3,
0,0,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,0,2,
1,1,3,
0,0,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=1
POPUP Branch=1 s=0 n=2 rt=1
STACK:BEGIN
1,1,3,
0,0,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=1 s=1 n=3 rt=1
STACK:BEGIN
0,0,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=0 s=0 n=5 rt=2
STACK:BEGIN
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=0,STACK:BEGIN
0,0,2,
0,0,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=0
POPUP Branch=0 s=0 n=2 rt=0
STACK:BEGIN
0,0,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,0,2,
0,0,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=1
POPUP Branch=1 s=0 n=2 rt=1
STACK:BEGIN
0,0,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=0 s=0 n=4 rt=1
STACK:BEGIN
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,1,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=0,STACK:BEGIN
0,0,3,
1,1,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=1
POPUP Branch=0 s=0 n=3 rt=1
STACK:BEGIN
1,1,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,1,3,
1,1,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=0,STACK:BEGIN
0,0,2,
1,1,3,
1,1,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=0
POPUP Branch=0 s=0 n=2 rt=0
STACK:BEGIN
1,1,3,
1,1,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
branch=1,STACK:BEGIN
1,0,2,
1,1,3,
1,1,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Print $$n<2, n=1
POPUP Branch=1 s=0 n=2 rt=1
STACK:BEGIN
1,1,3,
1,1,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=1 s=1 n=3 rt=1
STACK:BEGIN
1,1,4,
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=1 s=1 n=4 rt=2
STACK:BEGIN
1,2,5,
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=1 s=2 n=5 rt=3
STACK:BEGIN
1,3,6,
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
POPUP Branch=1 s=3 n=6 rt=5
STACK:BEGIN
STACK:END
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
We have the previous Result!!
Result is :8