poj 图相关之1094Sorting It All Out

poj 图相关之1094Sorting It All Out
Accepted 144K 0MS
测试数据http://poj.org/showmessage?message_id=133905
我个人觉得这道题有很大的bug，最开始我的代码是这样的，测试数据的第六个显示的是
Inconsistency found after 26 relations.
因为在前25个确实能够排好序，但是第26的时候就出现了Inconsistency（我的check函数就是用作这个的），但是其实这道题其实这要排好序了就用管后面的数据是否Inconsistency了，所以根据题意第6组数据的结果显示为：
Sorted sequence determined after 25 relations: ABCDEFGHIJKLMNOPQRSTUVWXYZ.
ac的版本：

#include<iostream>#include<cstring>#include<string>#include<cstdio>#include<math.h>#include<algorithm>#include<memory.h>#include<vector>#include<queue>#include<map>using namespace std;int n, m, degree[26];vector<int> vec[26];vector<int> result;bool mark[26], vis[26];int TopSort(int tmp){    int i, j, k, count, idx, tmpdegree[26], flag;    result.clear();    memset(vis, 0, sizeof(vis));    for (i = 0; i < 26; i++)        tmpdegree[i] = degree[i];    flag = 1;    for (i = 0; i < tmp; i++)    {        count = 0;        idx = -1;        for (j = 0; j < 26; j++)        {            if (!tmpdegree[j] && mark[j] && !vis[j])            {                count++;                idx = j;            }        }        if (!count)        {            return 0;        }        else        {            if (count > 1)                flag = 2;            result.push_back(idx);            vis[idx] = 1;            for (k = 0; k < vec[idx].size(); k++)            {                tmpdegree[vec[idx][k]]--;            }        }    }    if (flag == 2)        return 2;    else        return 1;}int main(){    //freopen("1.txt", "r", stdin);    int i, j, t, Cases, tm, it;    bool flag;    char tmp[20];    while (scanf("%d%d", &n, &m) != EOF && (n || m))    {        for (i = 0; i < 26; i++)            vec[i].clear();        memset(mark, 0, sizeof(mark));        memset(degree, 0, sizeof(degree));        tm = 0;        t = 2;        for (i = 0; i < m; i++)        {            scanf("%s", tmp);            vec[tmp[0] - 'A'].push_back(tmp[2] - 'A');            if (!mark[tmp[0] - 'A'])            {                mark[tmp[0] - 'A'] = 1;                tm++;            }            if (!mark[tmp[2] - 'A'])            {                mark[tmp[2] - 'A'] = 1;                tm++;            }            degree[tmp[2] - 'A']++;            t = TopSort(tm);            //t为0表示有环 为1表示有唯一排序 为2表示没有唯一排序            if (t == 0)                break;            if (t == 1 && result.size() == n)            {                flag = 1;                for (j = i+1; j < m; j++)                {                    scanf("%s", tmp);                }                printf("Sorted sequence determined after %d relations: ", i + 1);                for (j = 0; j < result.size(); j++)                    printf("%c", char(result[j] + 'A'));                printf(".\n");                break;            }        }        if (t == 0)        {            for (j = i+1; j < m; j++)                scanf("%s", tmp);            printf("Inconsistency found after %d relations.\n", i + 1);        }        else if (t == 2)        {            printf("Sorted sequence cannot be determined.\n");        }        else if (t == 1 && result.size() != n)        {            printf("Sorted sequence cannot be determined.\n");        }    }}

个人觉得对的版本：

#include<iostream>#include<cstring>#include<string>#include<cstdio>#include<math.h>#include<algorithm>#include<memory.h>#include<vector>#include<queue>#include<map>using namespace std;int n, m, degree[26];vector<int> vec[26];vector<int> result;bool mark[26], vis[26];int TopSort(int tmp){    int i, j, k, count, idx, tmpdegree[26], flag;    result.clear();    memset(vis, 0, sizeof(vis));    for (i = 0; i < 26; i++)        tmpdegree[i] = degree[i];    flag = 1;    for (i = 0; i < tmp; i++)    {        count = 0;        idx = -1;        for (j = 0; j < 26; j++)        {            if (!tmpdegree[j] && mark[j] && !vis[j])            {                count++;                idx = j;            }        }        if (!count)        {            return 0;        }        else        {            if (count > 1)                flag = 2;            result.push_back(idx);            vis[idx] = 1;            for (k = 0; k < vec[idx].size(); k++)            {                tmpdegree[vec[idx][k]]--;            }        }    }    if (flag == 2)        return 2;    else        return 1;}bool check(char*tmp){    char a, b;    int i, j, t;    i = j = -1;    for (t = 0; t < result.size(); t++)    {        if (tmp[0] - 'A' == result[t])            i = t;        if (tmp[2] - 'A' == result[t])            j = t;    }    if (i == -1 || j == -1 || i < j)        return true;    return false;}int main(){    //freopen("1.txt", "r", stdin);    int i, j, t, Cases, tm, it;    bool flag;    char tmp[20];    while (scanf("%d%d", &n, &m) != EOF && (n || m))    {        for (i = 0; i < 26; i++)            vec[i].clear();        memset(mark, 0, sizeof(mark));        memset(degree, 0, sizeof(degree));        tm = 0;        t = 2;        for (i = 0; i < m; i++)        {            scanf("%s", tmp);            vec[tmp[0] - 'A'].push_back(tmp[2] - 'A');            if (!mark[tmp[0] - 'A'])            {                mark[tmp[0] - 'A'] = 1;                tm++;            }            if (!mark[tmp[2] - 'A'])            {                mark[tmp[2] - 'A'] = 1;                tm++;            }            degree[tmp[2] - 'A']++;            t = TopSort(tm);            //t为0表示有环 为1表示有唯一排序 为2表示没有唯一排序            if (t == 0)                break;            if (t == 1 && result.size() == n)            {                flag = 1;                for (j = i+1; j < m; j++)                {                    scanf("%s", tmp);                    if (flag)                    {                        if (!check(tmp))                        {                            flag = 0;                            it = j;                        }                    }                }                if (!flag)                {                    printf("Inconsistency found after %d relations.\n", it + 1);                }                else                {                    printf("Sorted sequence determined after %d relations: ", i + 1);                    for (j = 0; j < result.size(); j++)                        printf("%c", char(result[j] + 'A'));                    printf(".\n");                }                break;            }        }        if (t == 0)        {            for (j = i+1; j < m; j++)                scanf("%s", tmp);            printf("Inconsistency found after %d relations.\n", i + 1);        }        else if (t == 2)        {            printf("Sorted sequence cannot be determined.\n");        }        else if (t == 1 && result.size() != n)        {            printf("Sorted sequence cannot be determined.\n");        }    }}