1016 Numbers That Count

#include <iostream>
#include <sstream>
#include <iomanip>
#include <string>
#include <numeric>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <bitset>
#include <utility>
#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
 
using namespace std;
typedef long long ll;
const int MAXN = 100;
const int MOD7 = 1000000007;
const int MOD9 = 1000000009;
const int INF = 2000000000;//0x7fffffff
const double EPS = 1e-9;
const double PI = 3.14159265358979;
const int dir_4r[] = { -1, 1, 0, 0 };
const int dir_4c[] = { 0, 0, -1, 1 };
const int dir_8r[] = { -1, -1, -1, 0, 0, 1, 1, 1 };
const int dir_8c[] = { -1, 0, 1, -1, 1, -1, 0, 1 };
 
int cnt[MAXN];
char digits[MAXN];
char buf1[MAXN];
char buf2[MAXN];
bool loop;//判断是否出现环
int loopsize;
map<string, int> mp;
 
void fun(char *str, int &index, int cnt) {
    if (cnt == 0)
        return;
    int d = cnt % 10;
    cnt /= 10;
    fun(str, index, cnt);
    str[index++] = d + ‘0‘;
}
 
void inventory(char *in, char *out) {
    memset(cnt, 0, sizeof(cnt));
    for (int i = 0; in[i]; ++i)
        cnt[in[i] - ‘0‘]++;
 
    int index = 0;
    for (int i = 0; i < 10; ++i) {
        if (cnt[i]) {
            fun(out, index, cnt[i]);
            out[index++] = i + ‘0‘;
        }
    }
    out[index++] = ‘\0‘;
}
 
bool isSelfInventory(char *buf1, char *buf2) {
    inventory(buf1, buf2);
    if (strcmp(buf1, buf2) == 0)
        return true;
    else
        return false;
}
 
int solve() {
    int index = 0;
    map<string, int>::iterator it;
    mp.clear();
 
    loop = false;
    loopsize = INF;
    strcpy(buf1, digits);
    while (index <= 15) {
        if (isSelfInventory(buf1, buf2))
            break;
        it = mp.find(string(buf1));
        if (it != mp.end()) {
            loop = true;
            loopsize = min(loopsize, index - it->second);
        }
 
        mp[string(buf1)] = index++;
        strcpy(buf1, buf2);
    }
    return index;
}
 
int main() {
    while (scanf("%s", digits)) {
        if (digits[0] == ‘-‘)
            break;
 
        int ans = solve();
        if (ans == 0)
            printf("%s is self-inventorying\n", digits);
        else if (ans <= 15)
            printf("%s is self-inventorying after %d steps\n", digits, ans);
        else if (loop)
            printf("%s enters an inventory loop of length %d\n", digits, loopsize);
        else
            printf("%s can not be classified after 15 iterations\n", digits);
    }
 
    //system("pause");
    return 0;
}