C # recursion

First, the concept of conception:

The function body calls the function itself until a condition is met and no further calls are continued.

Second, should meet the conditions factor:

(1) There is a process of repeated execution (call itself);

(2) There are conditions for jumping out of the process of repeated execution (function exit)

Third, example example

Calculation of factorial n! = N (n-1) * (n-2) * (n-3)*... * ( n>0 )

Iv. Precautions Notice:

1. There must be a loop-over condition in the recursion.

2, each call of the recursive function needs the stack to store, if the number of times too many words easily cause stack overflow.

Examples//A flock of sheep rushed to the villages to sell, each lost a village before the total number of 1/2 1, after 7 villages left two, asked how many sheep originally driven outclasshanshu{ Public intDgqiuyang (intCun//To seek the sheep by hand        {            intsum =0; if(Cun = =7)            {                return 2; } Sum=2* (Dgqiuyang (Cun +1) +1);//The initial cun=1 does not satisfy the marginal condition, always calls Cun+1,//until meet cun==7, get value Dgqiuyang (7) = ' 2 ' sheep//number of sheep in the 6th village Dgqiuyang (6) =2* (Dgqiuyang (7) +1) =2* (2+1) = 6 Sheep//number of sheep in the 5th village Dgqiuyang (5) =2* (Dgqiuyang (6) +1) =2* (6+1) = 14 Sheep//repeat the above steps until the first village is counted, and the output sum is the result.             returnsum; }        Static voidMain (string[] args) {Hanshu HB=NewHanshu (); Doublex = Hb.dgqiuyang (1); Console.Write ("To seek the sheep by hand"+x);           Console.ReadLine (); }}

C # recursion