-(void)touchesBegan:(nonnull NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event{

//算法入口

[self func2:9];

}

//计算阶乘  factor（m）＝ m！

-(int)factor:(int)m{

int factorNum=0;

if(m==0|m==1)

return 1;

else{

factorNum=m*[self factor:m-1];

NSLog(@"%d",factorNum);

return factorNum;

}

}

//计算  func1(m)  ＝ 1！＋3！＋5！＋... +m!

-(int)func1:(int)m{

int sum=0;

for (int i=1; i<=m; i=i+2) {

sum +=[self factor:i];

}

NSLog(@"%d",sum);

return sum;

}

//计算最终和   func2（m）＝1！+（1！+3！）+（1！+3！+5！) + ( 1! + 3! + 5! + 7! + 9!)＋....＋（1！+3！+5！＋ ... + m!）

-(int)func2:(int)m{

int sum=0;

for (int i=1; i<=m; i=i+2) {

sum +=[self func1:i];

}

NSLog(@"最终结果为：%d",sum);

return sum;

}