leetcode[69]Sqrt(x)
1959 ワード
Implement
Compute and return the square root of x.
int sqrt(int x) . Compute and return the square root of x.
class Solution {
public:
int sqrt(int x)
{
long long left=0,right=x/2+1;
while(left<=right)
{
long long mid=(left+right)/2;
if(mid*mid<=x&&(mid+1)*(mid+1)>x)return (int)mid;
else if(mid*mid<x) left=mid+1;
else right=mid-1;
}
}
/**
int sqrt(int x)
{
if(x==0)return 0;
double pre=0,cur=1;
while(abs(cur-pre)>0.00001)
{
pre=cur;
cur=(pre+x/pre)/2;
}
return int(cur);
}
*/
};