U-21

Description
Mike is very lucky, as he has two beautiful numbers, 3 and 5. But he is so greedy that he wants infinite beautiful numbers. So he declares that any positive number which is dividable by 3 or 5 is beautiful number. Given you an integer N (1 <= N <= 100000), could you please tell mike the Nth beautiful number?
Input
The input consists of one or more test cases. For each test case, there is a single line containing an integer N.
Output
For each test case in the input, output the result on a line by itself.
Sample Input
1
2
3
4


Sample Output
3
5

6

9

题意描述：

多组数据进行测试，输入一个整数n输入对应的第n个能被3或5整除的数。

解题思路：

一开始想到用for循环，但是最大数不能进行确定，所以此方法不行。可以先定义一个数为3，加一之后看是否符合！然后在相加，直到符合条件的数大于1000000。

解题细节：

不用for循环，先将1000000以内符合条件的算出来，在输入第n个时，别忘了需要减一，即n-1。

代码：

#include<bits/stdc++.h>using namespace std;int main(){vector<int>v;int n,i=3,m;v.clear();while(1){if(n>1000000)break;if(i%3==0||i%5==0){v.push_back(i);n++;}i++;}while(cin>>m){cout<<v[m-1]<<endl;}return 0;}

心得：

开发思修，培养独立做题能力！！加油