POJ 1208 The Blocks Problem (模拟)

很烦人的一道模拟（似乎所有的模拟都这样~~~），用block[][]来记录各个block列的状态，b_n[]保存各个列的高度,b_ind[]用于查找第i个block所在的列，a_h,b_h是a·b其在block列的高度,a_p,b_p是a,b所在的列数。写完代码一交WA，改了20多分钟，才发现漏了++b_n[b_p]~~~~做题要细心，写代码更要细心！

#include <iostream>
#include <cstdio>
#include <memory>
#include <algorithm>
using namespace std;

#define MAXN 100

int block[MAXN][MAXN],b_ind[MAXN],b_n[MAXN];
int n,a_p,b_p,a_h,b_h,tmp;
int init()
{
    int i,j;
    for(i = 0;i <= n; ++i)
    {
        block[i][0] = i;
        b_ind[i] = i;
        b_n[i] = 1;
    }
    return 0;
}
int move_onto(const int& a,const int& b)
{
    int i,j;
    for(i = a_h+1;i < b_n[a_p]; ++i)
    {
        block[block[a_p][i]][0] = block[a_p][i];
        b_n[block[a_p][i]] = 1;
        b_ind[block[a_p][i]] = block[a_p][i];
    }
    b_n[a_p] = a_h;
    for(i = b_h+1;i < b_n[b_p]; ++i)
    {
        block[block[b_p][i]][0] = block[b_p][i];
        b_n[block[b_p][i]] = 1;
        b_ind[block[b_p][i]] = block[b_p][i];
    }
    b_n[b_p] = b_h+2;
    b_ind[a] = b_p;
    block[b_p][b_h+1] = a;
    return 0;
}
int move_over(const int& a,const int& b)
{
    int i,j;
    for(i = a_h+1;i < b_n[a_p]; ++i)
    {
        block[block[a_p][i]][0] = block[a_p][i];
        b_n[block[a_p][i]] = 1;
        b_ind[block[a_p][i]] = block[a_p][i];
    }
    b_n[a_p] = a_h;
    b_ind[a] = b_p;
    block[b_p][b_n[b_p]] = a;
    ++b_n[b_p];
    return 0;
}
int pile_onto(const int& a,const int& b)
{
    int i,j;
    for(i = b_h+1;i < b_n[b_p]; ++i)
    {
        block[block[b_p][i]][0] = block[b_p][i];
        b_n[block[b_p][i]] = 1;
        b_ind[block[b_p][i]] = block[b_p][i];
    }
    b_n[b_p] = b_h+1;
    for(i = a_h; i < b_n[a_p]; ++i)
    {
        block[b_p][b_n[b_p]] = block[a_p][i];
        b_ind[block[a_p][i]] = b_p;
        ++b_n[b_p];
    }
    b_n[a_p] = a_h;
    return 0;
}
int pile_over(const int& a,const int& b)
{
    int i,j;
    for(i = a_h;i < b_n[a_p]; ++i)
    {
        block[b_p][b_n[b_p]] = block[a_p][i];
        ++b_n[b_p];
        b_ind[block[a_p][i]] = b_p;
    }
    b_n[a_p] = a_h;
    return 0;
}
int main()
{
    int i,j,a,b;
    char s1[10],s2[10];
    char s_move[]="move",s_pile[]="pile",s_onto[]="onto",s_over[]="over";
    char s_quit[] = "quit";
    while(scanf("%d",&n) != EOF)
    {
        init();
        while(true)
        {
            scanf("%s",s1);
            if(!strcmp(s1,s_quit))
                break;
            scanf("%d%s%d",&a,s2,&b);
            a_p = b_ind[a];
            b_p = b_ind[b];
            if(a_p==b_p)
                continue;
            a_h = b_h = 0;
            j = 0;
            while(1)
            {
                if(block[a_p][j] == a)
                    break;
                ++j;
            }
            a_h = j;
            j = 0;
            while(1)
            {
                if(block[b_p][j] == b)
                    break;
                ++j;
            }
            b_h = j;
            if(!strcmp(s1,s_move))
            {
                if(!strcmp(s2,s_onto))
                    move_onto(a,b);
                else
                    move_over(a,b);
            }else
            {
                if(!strcmp(s2,s_onto))
                    pile_onto(a,b);
                else
                    pile_over(a,b);
            }
        }
        for(i = 0;i < n; ++i)
        {
            cout<<i<<":";
            for(j = 0;j < b_n[i]; ++j)
                cout<<' '<<block[i][j];
            cout<<endl;
        }
    }
    return 0;
}