2014遼寧省賽 Repeat Number

問題 C: Repeat Number

時間限制: 1 Sec 內存限制: 128 MB
提交: 23 解決: 7
[提交][狀態][論壇]

題目描述

Definition: a+b = c, if all the digits of c are same ( c is more than ten)，then we call a and b are Repeat Number. My question is How many Repeat Numbers in [x,y].

輸入

There are several test cases.

Each test cases contains two integers x, y(1<=x<=y<=1,000,000) described above.

Proceed to the end of file.

輸出

For each test output the number of couple of Repeat Number in one line.

樣例輸入

1 10 10 12

樣例輸出

5 2

提示

If a equals b, we can call a, b are Repeat Numbers too, and a is the Repeat Numbers for itself.

這道題，我是暴力加二分過的，枚舉c的可能值即可。然後求中間點與邊界差的最小值即可

#include
#include
#include
#include
#include
#include
using namespace std;
vector G;
void init()
{
    int k=1;
    for(int i=0;i<6;i++)
    {
        k=k*10+1;
        for(int j=1;j<=9;j++)
            G.push_back(k*j);
    }
}
int main()
{
    int x,y;
    init();
    while(cin>>x>>y)
    {
        int p=lower_bound(G.begin(),G.end(),2*x)-G.begin();
        int q=lower_bound(G.begin(),G.end(),2*y)-G.begin();
        int ans=0;
        //for(int i=0;i<10;i++)
         //   cout<2*y) q--;
       // cout<