POJ_1112_Team Them Up!

#include <iostream>
#define inf 1000000
using namespace std;
const int MAXN = 101;
int map[MAXN][MAXN];
int id[2][MAXN];
int color[MAXN];
int dp[MAXN][MAXN];
int tmp[MAXN][MAXN];
struct  
{
    int c1, c2;
    int i, j;
}pre[MAXN][MAXN];
int N, t;
bool DFS(int CurV, int c)
{
    color[CurV] = c;
    id[c%2][t]++;
    bool ans = true;
    for (int i = 1; i <= N; i++)
    {
        if (map[CurV][i] == 1)
        {
            if (color[i] == -1)
            {
                ans = DFS(i, (c%2==0)?(c+1):(c-1));
                if (ans == false)
                    return false;
            }
            else if (color[i] == color[CurV])
                return false;
        }
    }
    return true;
}
int main()
{
    freopen("test.txt", "r", stdin);
    scanf("%d", &N);
    memset(map, 0, sizeof(map));
    memset(id, 0, sizeof(id));
    memset(color, 0xff, sizeof(color));
    memset(tmp, 0, sizeof(tmp));
    memset(dp, 0, sizeof(dp));
    
    for (int i = 1; i <= N; i++)
    {
        int j;
        while (scanf("%d", &j) != EOF && j != 0)
            tmp[i][j] = 1;
    }
    for (int i = 1; i <= N; i++)
    {
        for (int j = i+1; j <= N; j++)
        {
            if (!(tmp[i][j] == 1 && tmp[j][i] == 1))
                map[i][j] = map[j][i] = 1;
        }
    }
    bool ans;
    int c = 0;
    t = 0;
    for (int i = 1; i <= N; i++)
    {
        if (color[i] == -1)
        {
            ans = DFS(i, c);
            c += 2;
            t++;
            if (ans == false)
                break;
        }
    }
    if (ans == false)
        printf("No solution\n");
    else
    {
        int n = 0;
        dp[0][0] = 1;
        for (int k = 0; k < t; k++)
        {
            for (int i = 0; i <= n; i++)
            {
                int j = n-i;
                if (dp[i+id[0][k]][j+id[1][k]] == 0 && dp[i][j] == 1)
                {
                    pre[i+id[0][k]][j+id[1][k]].c1 = k*2;
                    pre[i+id[0][k]][j+id[1][k]].c2= k*2+1;
                    pre[i+id[0][k]][j+id[1][k]].i = i;
                    pre[i+id[0][k]][j+id[1][k]].j = j;
                    dp[i+id[0][k]][j+id[1][k]] = 1;
                }
                if (dp[i+id[1][k]][j+id[0][k]] == 0 && dp[i][j] == 1)
                {
                    pre[i+id[1][k]][j+id[0][k]].c1 = k*2+1;//记录颜色
                    pre[i+id[1][k]][j+id[0][k]].c2 = k*2;//记录颜色
                    pre[i+id[1][k]][j+id[0][k]].i = i;
                    pre[i+id[1][k]][j+id[0][k]].j = j;
                    dp[i+id[1][k]][j+id[0][k]] = 1;
                }
            }
            n += id[0][k]+id[1][k];
        }
        int res = inf;
        int a, b;
        for (int i = 1; i <= N; i++)
        {
            int j = N-i;
            if (dp[i][j] == 1 && res > abs(i-j))
            {
                a = i;
                b = j;
                res =  abs(i-j);    
            }
        }
        printf("%d", a);
        for (int i = a, j = b; !(i == 0 && j == 0);)
        {
            int c = pre[i][j].c1;
            for (int k = 1; k <= N; k++)
            {
                if (color[k] == c)
                    printf    (" %d", k);
            }
            int _i = i;
            i = pre[i][j].i;
            j = pre[_i][j].j;
        }
        printf("\n");
        printf("%d", b);
        for (int i = a, j = b; !(i == 0 && j == 0);)
        {
            int c = pre[i][j].c2;
            for (int k = 1; k <= N; k++)
            {
                if (color[k] == c)
                    printf    (" %d", k);
            }
            int _i = i;
            i = pre[i][j].i;
            j = pre[_i][j].j;
        }
        printf("\n");
    }
    return 0;
}