蓝桥杯 问题 1434: [蓝桥杯][历届试题]回文数字

题目

一道很easy的题，使用递归解决有33%的错误

望路过的大佬指点一二

代码如下：

#include <iostream>
#include <cstring>
using namespace std;
int A[6],B[10000];
int sum,ccount;

void dfs(int cur,int cursum,int digit)
{
	if (cur == (digit % 2 ? (digit + 1) / 2 : digit / 2) &&cursum==sum)
	{
		int flag=0;
		for (int j = 0; j < digit; j++)
		{
			flag = flag*10+A[j];
		}
		B[ccount++] = flag;
		return;
	}
	if (cur > (digit % 2 ? (digit + 1) / 2 : digit / 2))
		return;
	int i;
	cur == 0 ? i = 1 : i = 0;
	for (; i <=9; i++)
	{
		A[cur] = A[digit-cur-1]=i;
		if(cur== digit - cur - 1)
			dfs(cur + 1, cursum + A[cur], digit);
		else
			dfs(cur + 1, cursum + 2*A[cur], digit);	
	}
}
int main()
{
	cin >> sum;
	ccount = 0;
	dfs(0,0,5);
	memset(A, 0, sizeof(A));
	dfs(0, 0, 6);
	if (ccount == 0)
	{
		cout << -1 << endl;
	}
	else
	{
		for (int i = 0; i < ccount; i++)
		{
			cout << B[i] << endl;
		}
	}
	return 0;
}

无奈之下用了暴力：

代码如下：

#include <iostream>
#include <cstring>
using namespace std;

int main()
{
	int sum;
	cin >> sum;
	int flag=0;
	for (int i = 1; i <= 9; i++)
	{
		for (int j = 0; j <= 9; j++)
		{
			for (int k = 0; k <= 9; k++)
			{
				if ((2 * i + 2 * j + k) == sum)
				{
					flag = 1;
					cout << i << j << k << j << i << endl;
				}
			}
		}
	}
	for (int i = 1; i <= 9; i++)
	{
		for (int j = 0; j <= 9; j++)
		{
			for (int k = 0; k <= 9; k++)
			{
				if ((2 * i + 2 * j + 2*k) == sum)
				{
					flag = 1;
					cout << i << j << k << k << j << i << endl;
				}
			}
		}
	}
	if (flag == 0)
		cout << -1 << endl;
	return 0;
}