Объясните пожалуйста код))
#include <map>
#include <string>
#include <stdio.h>
#include <string.h>
#include <list>

#define INPUT_FILE      "input.txt"
#define ROOT            std::string("Isenbaev")
#define EMPTY           std::string("")
#define MAXN            128
#define INF             666666

int N;
std::map<std::string, int> Sol; // solution number for each team contestant
struct Team
{
        std::string names[3];
        bool isRoot;
} Teams[MAXN];


std::string TieTeams(int t1, int t2)
{
        int i, j;

        if (t1 == t2)
                return EMPTY;
        for (i = 0; i < 3; i++)
                for (j = 0; j < 3; j++)
                        if (Teams[t1].names[i] == Teams[t2].names[j])
                        {
                                return Teams[t1].names[i];
                        }
        return EMPTY;
}

void BF(int start_team)
{
        int i, node;
        std::string sTieMember, sName;
        std::list<int> queue;
        std::list<std::string> qMember;
        bool bContinue;

        node = start_team;
        queue.clear();
        queue.push_back(node);
        qMember.push_back(ROOT);
        Sol[ROOT] = 0;

        do
        {
                node = queue.front();
                sTieMember = qMember.front();

                queue.pop_front();
                qMember.pop_front();

                bContinue = false;
                /* we have a team. Fill rest of members of it with +1 of the sTieMember if this makes it better */
                for (i = 0; i < 3; i++)
                {
                        sName = Teams[node].names[i];
                        if (sName != sTieMember && Sol[sName] > Sol[sTieMember] + 1)
                        {
                                Sol[sName] = Sol[sTieMember] + 1;
                                /* we improved it, add neighboring teams in the queue */
                                bContinue = true;
                        }
                }

                /* find a team which ties with current one. If we improved this team, add those to queue */
                if (bContinue)
                        for (i = 0; i < N; i++)
                        {
                                sName = TieTeams(node, i);

                                if (sName != EMPTY)
                                {
                                        queue.push_back(i);
                                        qMember.push_back(sName);
                                }
                        }
        }
        while (queue.size() > 0);
}


int main()
{
        int i, j;
        char sz[32];


#ifndef ONLINE_JUDGE
        freopen(INPUT_FILE, "rt", stdin);
#endif
        scanf("%d\n", &N);

        Sol.clear();

        for (i = 0; i < N; i++)
        {
                Teams[i].isRoot = false;

                for (j = 0; j < 3; j++)
                {
                        scanf("%s", &sz);
                        Teams[i].names[j] = sz;
                        Sol[sz] = INF;
                        
                        if (ROOT == sz)
                                Teams[i].isRoot = true;
                }
        }

        /* make a BF from each root team */
        for (i = 0; i < N; i++)
                if (Teams[i].isRoot)
                {
                        BF(i);
                }

        /* output results */
        std::map<std::string, int>::iterator iter;

        for (iter = Sol.begin(); iter != Sol.end(); iter ++)
        {
                printf("%s ", iter->first.c_str());
                if (iter->second == INF)
                        printf("undefined\n");
                else
                        printf("%d\n", iter->second);
                
        }

        return 0;
}

Для домашних заданий, курсовых, существует "Центр Помощи".

Тема перенесена! 

Ключевые места автор программы не поленился и выделил

// solution number for each team contestant
/* we have a team. Fill rest of members of it with +1 of the sTieMember if this makes it better */
/* we improved it, add neighboring teams in the queue */
/* find a team which ties with current one. If we improved this team, add those to queue */

Я который раз уже замечаю, что англичане черта с два пишут в повседневной практике комментарии как мы. Потому что:
-они писали языки программирования достаточно внятно с самого начала и им порой вообще не надо комментировать код, они и так всё видят по названиям операторов.

               

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