Novice Diary-January 23
Case number one:
Multi-branch recursion, Fibonacci sequence
Use code to find the value of a certain Fibonacci sequence
Fibonacci sequence: The value of this term is equal to the sum of the first two terms
such as: 1,1,2,3,5,8,13...
分解成两个子问题,f5(n-1)和f5(n-2)
static int f5(int n){
if (n == 1 || n == 2){
return 1;
}
return f5(n - 1) + f5(n - 2);
}
Effect picture:
Case 2:
Find the greatest common divisor
m continues to take the remainder of n, until n=0,
default m> n
static int f6(int m,int n){
if (n == 0){
return m;
}
return f6(n,m % n);
}
Effect picture:
Case three:
Insertion sort
static void f7(int[] array,int k){
if (k == 0){
return;
}
int x = array[k];
int index = k - 1;
f7(array,k-1);
while (x < array[index] && index > -1){
array[index + 1] = array[index];
index--;
}
array[index + 1] = x;
}
Case Four:
Print the travel path of the Tower of Hanoi
static void printHanoiTower(int N,String from,String to,String help){
if (N == 1){
System.out.println("移动 " + N + "号盘子 " + from + " --> " + to);
return;
}
//将1 ~ N-1个盘子从A柱移动到C柱，B作为辅助柱子(这里的移动并不是指直接移动)
printHanoiTower(N - 1,from,help,to);
//打印将N号盘子从A柱移动到B柱
System.out.println("移动 " + N + "号盘子 " + from + " --> " + to);
//将1 ~ N-1个柱子从C柱移动到B柱,A作为辅助柱子
// (B柱此时放的柱子N最大,可以继续放任意柱子,所以可以视为空)
printHanoiTower(N - 1,help,to,from);
}
}
Effect picture:
