poj3100

本来想到二分查找，后来发现直接使用pow,floor和ceil就可以。这些函数在cmath中。

View Code

#include <iostream>
#include <cstdlib>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;

int main()
{
freopen("D:\\t.txt", "r", stdin);
int b, n;
while (scanf("%d%d", &b, &n) != EOF && !(b == 0 && n == 0))
{
double a = pow(b, 1.0 / n);
int a1, a2;
a1 = (int) floor(a);
a2 = (int) ceil(a);
int d1 = abs((int) pow((double) a1, n) - b);
int d2 = abs((int) pow((double) a2, n) - b);
if (d1 > d2)
printf("%d\n", a2);
else
printf("%d\n", a1);
}
return 0;
}

转载于:https://www.cnblogs.com/rainydays/archive/2011/02/28/1966841.html