Cod sursa(job #2226528)

Utilizator inquisitorAnders inquisitor Data 30 iulie 2018 12:11:08
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 2.24 kb
#include <bits/stdc++.h>

int muchii[1000010];
int degree[100010];
char level[100010];
int Q[100010], qs, qe;

inline int get_int()
{
    int nr = 0, c = getchar();

    for(; c < 48 | c > 57; c = getchar());

    for(; c > 47 & c < 58; nr = nr * 10 + c - 48, c = getchar());

    return nr;
}

void BFS(int s)
{
    memset(level, 0xFF, sizeof level);

    qs = qe = 0;

    level[s] = 0;

    Q[qe++] = s;

    while(qs < qe)
    {
        int t = Q[qs++];

        for(int it = degree[t], tar = degree[t + 1]; it != tar; ++it)
        {
            int v = muchii[it];

            if(level[v] >= 0) continue;

            level[v] = level[t] + 1;

            Q[qe++] = v;
        }
    }
}

char buffer[20000000]; int p = -1;

__attribute__((always_inline)) void put_int(int x)
{
    if(x == -1)
    {
        buffer[++p] = '-'; buffer[++p] = '1'; buffer[++p] = ' ';

        return;
    }

    int digits =  x > 0x3B9AC9FF ? 0xB :
                  x > 0x5F5E0FF  ? 0xA :
                  x > 0x98967F   ? 0x9 :
                  x > 0xF423F    ? 0x8 :
                  x > 0x1869F    ? 0x7 :
                  x > 0x270F     ? 0x6 :
                  x > 0x3E7      ? 0x5 :
                  x > 0x63       ? 0x4 :
                  x > 0x9        ? 0x3 : 0x2;

    for(int i = digits; --i; x /= 0xA)
    {
        buffer[p + i] = x % 0xA + 0x30;
    }

    buffer[p = p + digits] = 0x20;
}

int main()
{
    freopen("bfs.in", "r", stdin);
    freopen("bfs.out", "w", stdout);

    int N, M, start, u, v;

    N = get_int();

    M = get_int();

    start = get_int();

    for(int i = 0; i < M; ++i)
    {
        u = get_int();

        v = get_int();

        ++degree[u];
    }

    for(int i = 1; i <= N; ++i)
    {
        degree[i] += degree[i - 1];
    }

    degree[N + 1] = M;

    freopen("bfs.in", "r", stdin);

    N = get_int();

    M = get_int();

    start = get_int();

    for(int i = 0; i < M; ++i)
    {
        u = get_int();

        v = get_int();

        muchii[--degree[u]] = v;
    }

    BFS(start);

    for(int i = 1; i <= N; ++i)
    {
        put_int(level[i]);
    }

    fwrite(buffer, 1, p, stdout);

    return 0;
}