poj1416 Shredding Company

思路：

搜索。

实现：

#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <cstring>
using namespace std;

const int INF = 0x3f3f3f3f;

vector<int> num;
int n, x, y, maxn, ansn;
bool split[10];
int ans[10], buf[10], cnt_m = 0;

void dfs(int now, bool f)
{
    if (now == n)
    {
        int sum = 0;
        split[n - 1] = true;
        int cnt = 0, t = 0;
        for (int i = 0; i < n; i++)
        {
            cnt += num[i];
            if (split[i])
            {
                sum += cnt;
                buf[t++] = cnt;
                cnt = 0;
            }
            else
                cnt *= 10;
        }
        if (sum <= x)
        {
            if (sum > maxn)
            {
                maxn = sum;
                ansn = t;
                for (int i = 0; i < ansn; i++)
                {
                    ans[i] = buf[i];
                }
            }
            else if (sum == maxn && f)
            {
                cnt_m++;
            }
        }
        return;
    }
    split[now] = true;
    dfs(now + 1, f);
    split[now] = false;
    dfs(now + 1, f);
}

int main()
{
    //freopen("C:\users\wangyiming\Desktop\in.txt", "r", stdin);
    while (cin >> x >> y, x || y)
    {
        num.clear();
        maxn = -INF;
        cnt_m = 0;
        memset(split, 0, sizeof(split));
        while (y)
        {
            num.push_back(y % 10);
            y /= 10;
        }
        n = num.size();
        reverse(num.begin(), num.end());
        dfs(0, false);
        dfs(0, true);
        if (cnt_m > 2) puts("rejected");
        else if (maxn != -INF)
        {
            cout << maxn << " ";
            for (int i = 0; i < ansn; i++)
            {
                cout << ans[i] << " ";
            }
            cout << endl;
        }
        else puts("error");
    }
    return 0;
}