201. bitwise and of numbers range

class  {
public:
    int rangeBitwiseAnd(int m, int n) {
        if(m==n)return m;
        int temp=1<<31;
        int result=0;
        for(int i=0;i<31;i++){
            if((m&temp)==(n&temp))result|=m&temp;
            temp>>=1;
        }
        return result; 
    }

};