Given positive integers B and N, find an integer A such that AN is as close as possible to B. (The result A is an approximation to the Nth root of B.) Note that AN may be less than, equal to, or greater than B.
Input: The input consists of one or more pairs of values for B and N. Each pair appears on a single line, delimited by a single space. A line specifying the value zero for both B and N marks the end of the input. The value of B will be in the range 1 to 1,000,000 (inclusive), and the value of N will be in the range 1 to 9 (inclusive).
Output: For each pair B and N in the input, output A as defined above on a line by itself.
1 #include <iostream> 2 #include <cmath> 3 #include <cstdlib> 4 using namespace std; 5 int main(){ 6 double b, n; 7 while(cin >> b >> n){ 8 if(b == 0 && n == 0) 9 break; 10 //pow:double pow(double, double) 11 int a = (int)pow(b, 1/ n);//直接取整，不是四舍五入 ,pow(a, n) < b 12 if(b - pow(a, n) < pow(a + 1, n) - b) 13 cout << a << endl; 14 else 15 cout << a + 1 << endl; 16 } 17 return 0; 18 }
| Example Input: | Example Output: |
| 4 3 5 3 27 3 750 5 1000 5 2000 5 3000 5 1000000 5 0 0 |
1 2 3 4 4 4 5 16 |