FZU 1912 Divisibility by Thirty-six（整除问题+字符串维护+贪心）

这个整除36的与整除45的完全一样,就是被4整除的有点多,但都是两位数,所以枚举后面两位就可以了.

#include <stdio.h>
#include <string.h>
#include <iostream>
#include <algorithm>
using namespace std;
const int N = ;
const int M = ;
const int dir[][] = { {, }, {, }, {, }, {, }, {, }, {, }, {, }, {, }, {, }, {, }, {, }, {, }, {, }, {, }, {, },

    {, }, {, }, {, }, {, }, {, }, {, }, {, }
};

int tmp, rec[M], cnt[M];
int n, s[N], x, id;
bool flag;
char ans[N];

void init()
{
    char num[N];
    scanf("%s", num);
    x = strlen(num), tmp = ;

    flag = false;
    memset(rec, , sizeof(rec));
    memset(ans, , sizeof(ans));

    for (int i = ; i < x; i++)
    {
        int cur = num[i] - '';
        tmp += cur;
        rec[cur]++;
    }
}
void put(int a[], int d, char *str)
{
    int len = ;
    for (int i = ; i >= ; i--)
    {
        for (int j = ; j < a[i]; j++)
            str[len++] = i + '';
    }
    for (int i = ; i < ; i++)
        str[len++] = dir[d][i] + '';
    str[len] = '\0';
}

bool cmp(char *a, char *b)
{
    for (int i = ; a[i]; i++)
    {
        if (a[i] != b[i]) return a[i] < b[i];
    }
    return false;
}

void judge(int m)
{

    char now[N];
    put(cnt, id, now);
    if (m < x || (cmp(ans, now) && m == x))
    {
        flag = true;
        x = m;
        strcpy(ans, now);
    }
}

void dfs(int m, int d, int sum)
{

    if (d >= m)
    {
        if ((sum - tmp) %  == )    judge(m);
        return;
    }

    for (int i = ; i <= ; i++)
    {
        if (!cnt[i]) continue;
        cnt[i]--;
        dfs(m, d + , sum + i);
        cnt[i]++;
    }
}

void search(int d)
{
    for (int i = ; i < ; i++)
    {
        cnt[dir[d][i]]--;
        if (cnt[dir[d][i]] < ) return;
    }
    id = d;
    for (int i = ; i <= tmp && i <= x; i++)
        dfs(i, , );
}

bool isOK(char *str)
{
    int sum = , len = strlen(str);
    if (len ==  && rec[] == ) return false;
    for (int i = ; i < len; i++)
        sum += str[i] - '';
    return !sum;
}

void solve()
{

    for (int i = ; i < ; i++)
    {
        memcpy(cnt, rec, sizeof(rec));
        search(i);
    }
    if (isOK(ans)) printf("0\n");
    else if (flag) puts(ans);
    else printf("impossible\n");
}

int main()
{
    int cas;
    scanf("%d", &cas);
    for (int i = ; i <= cas; i++)
    {

        init();
        printf("Case %d: ", i);
        solve();
    }
    return ;
}