USACO 1.2 Dual Palindromes

题目连接

http://train.usaco.org/usacoprob2?a=FXd0kY3vFTM&S=dualpal

Description

A number that reads the same from right to left as when read from left to right is called a palindrome. The number 12321 is a palindrome; the number 77778 is not. Of course, palindromes have neither leading nor trailing zeroes, so 0220 is not a palindrome.

The number 21 (base 10) is not palindrome in base 10, but the number 21 (base 10) is, in fact, a palindrome in base 2 (10101).

Write a program that reads two numbers (expressed in base 10):

N (1 <= N <= 15)
S (0 < S < 10000)
and then finds and prints (in base 10) the first N numbers strictly greater than S that are palindromic when written in two or more number bases (2 <= base <= 10).
Solutions to this problem do not require manipulating integers larger than the standard 32 bits.

Input

A single line with space separated integers N and S.

Output

N lines, each with a base 10 number that is palindromic when expressed in at least two of the bases 2..10. The numbers should be listed in order from smallest to largest.

Sample Input

3
25

Sample Output

26
27
28

题意

给出十进制数大于S的前N个数,他们在十进制以内存在两个以上的回文数。

题解

和上一题差不多的思路吧,变换进制检测即可,水题。

代码

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/*
ID: hyson601
PROG: dualpal
LANG: C++11
*/
#include <iostream>
using namespace std;
int n,s;
char now[35];
bool check(int num){
int base=2,length_now,cnt=0;
while(base<=10 && cnt<2){
int temp=num;
length_now=0;
while(temp){
now[length_now]=temp%base+'0';
length_now++;
temp/=base;
}
int flag=1;
for(int i=0;i<length_now/2 && flag;++i){
if(now[i]!=now[length_now-1-i])
flag=0;
}
++base;
if(!flag)
continue;
else
cnt++;
}
if(cnt>=2)
return true;
else
return false;
}
int main(){
freopen("dualpal.in","r",stdin);
freopen("dualpal.out","w",stdout);
scanf("%d%d",&n,&s);
int cnt=0;
++s;
while(cnt<n){
if(check(s)){
++cnt;
printf("%d\n",s);
}
++s;
}
}