一维数组纯模拟 #6 WA Help！

// LUOGU_RID: 102240633
#include <bits/stdc++.h>
#include <iostream>

using namespace std;

long long top, m;
long long block[105]; //内存条
long long block_1[105]; //内存条副本，用来defragment()

long long alloc(long long n)
{
    bool flag = false;
    long long start;
    for(long long i=1, j; i<=m; i++)
        if(block[i] == 0)
        {
            j = i;
            while(block[++j] == 0 && j < m);
            //cout<<"[j = "<<j<<" i = "<<i<<']'<<endl;
            if(j - i >= n)//内存够
            {
                flag = true;
                start = i;//空闲空间初始位置
                break;
            }
            i = j - 1;
        }
    //cout<<"flag = "<<flag<<endl;
    if(flag)//有空间存储
    {
        for(long long i=start; i<start+n; i++)
            block[i] = top;
        top++;
        return top-1;
    }
    else
        return -1;
}

bool erase(long long x)
{
    bool flag = false;
    for(long long i=1; i<=m; i++)
        if(block[i] == x)
        {
            block[i] = 0;
            flag = true;
            break;
        }
    return flag;
}

void defragment()
{
    for(long long i=1, j=1; i<=m; i++)
        if(block[i] != 0)
            block_1[j++] = block[i];//block数组缩进后存放到副本
    for(long long i=1; i<=m; i++)
        block[i] = block_1[i];//把副本复制回内存条
}

void print()
{
    for(long long i=1; i<=100; i++)
    {
        cout<<block[i]<<' ';
        if(i % 10 == 0)
            cout<<endl;
    }
}

int main()
{
    long long t;
    top++;
    cin>>t>>m;
    while(t--)
    {
        string operate;
        cin>>operate;
        if(operate[0] == 'd')
        {
            defragment();
            //print();
        }
        else
        {
            long long n;
            scanf("%lld",  &n);
            if(operate == "alloc")
            {
                long long flag = alloc(n);
                //print();
                if(flag == -1)
                    cout<<"NULL"<<endl;
                else
                    cout<<flag<<endl;
            }
            else
            {
                bool flag = erase(n);
                //print();
                if(!flag)
                    cout<<"ILLEGAL_ERASE_ARGUMENT"<<endl;
            }
        }
    }
    return 0;
}

print();是测试用的，没实际意义