D - Div 3
Time Limit:250MS Memory Limit:4096KB 64bit IO Format:%I64d & %I64u
Submit Status Practice SGU 105
Appoint description:
System Crawler (2015-01-20)
Description
There is sequence 1, 12, 123, 1234, ..., 12345678910, ... . Given first N elements of that sequence. You must determine amount of numbers in it that are divisible by 3.
Input
Input contains N (1<=N<=231 - 1).
Output
Write answer to the output.
Sample Input
4
Sample Output
2
#include<iostream> #include<cstdio> using namespace std; int main() { int n; while(scanf("%d",&n)!=EOF) { int ans=(n/3)*2+((n%3)==2?1:0); printf("%d\n",ans); } return 0; }
时间: 2024-09-30 12:13:57