【每日算法Day 67】经典面试题：手动开根号，你知道几种方法

classSolution {
public:
intmySqrt(intx) { 
longy=int(newtonSqrt(x)) +1;  
returny*y>x?y-1 : y;    }
doublenewtonSqrt(doublen) { 
doublex0=n;   
while (abs(x0*x0-n) >=1e-6) {    
x0=0.5*(n/x0+x0);
        }     
returnx0;
    }
doublebinarySqrt(doublen) {  
doublel=0, r=n;   
while (r-l>=1e-6) {   
doublem= (l+r)/2;   
if (m*m<n) l=m;   
elser=m;    
        }      
returnr; 
    }
// 超时  doublegdSqrt(doublen) {    
doublex0=n;  
while (abs(x0*x0-n) >=1e-6) {   
doublelr=min(1e-3, 1e-1*x0/(x0*x0-n));  
x0=x0-lr*(x0*x0-n); 
        }       
returnx0;  
    }
};