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FIFO算法 C++實作

話不多說直接放代碼吧…………

#include <iostream>
#include <cstring>
using namespace std;
void dayinwulikuai(int *wulikuai,int wulikuaicnt)
{
    int j;
    for(j=0;j<wulikuaicnt;j++)
    {
        if(wulikuai[j]!=-1)
        {
            cout<<"block"<<j+1<<"   "<<wulikuai[j]<<endl;
        }
        else
        {
            cout<<"block"<<j+1<<"   "<<endl;
        }
    }
}
int maxx(int *zhuliucnt,int wulikuaicnt)
{
    int zuida=0;
    int zuidaxiabiao=0;
    int t;
    for(t=0;t<wulikuaicnt;t++)
    {
        if(zhuliucnt[t]>zuida)
        {
            zuida=zhuliucnt[t];
            zuidaxiabiao=t;
        }
    }
    return zuidaxiabiao;
}
void tihuan(int dangqianpage,int *wulikuai,int wulikuaicnt,int *zhuliucnt)
{
    int xiabiao=maxx(zhuliucnt,wulikuaicnt);
    wulikuai[xiabiao]=dangqianpage;
    zhuliucnt[xiabiao]=0;
}
void insertpage(int dangqianpage,int *wulikuai,int wulikuaicnt,int *zhuliucnt)
{
    int k;
    int flag1=0;//标志實體塊中是否有已經存了該頁面的,0表示沒有
    int flag2=0;//标志是否還有沒存頁面的實體塊,0表示沒有,即不缺頁
    for(k=0;k<wulikuaicnt;k++)
    {
        if(wulikuai[k]==dangqianpage)
        {
            flag1=1;
            break;
        }
    }
    if(flag1==0)
    {
        for(k=0;k<wulikuaicnt;k++)
        {
            if(wulikuai[k]==-1)
            {
                flag2=1;
                wulikuai[k]=dangqianpage;
                break;
            }
        }
        if(flag2==0)
        {
            tihuan(dangqianpage,wulikuai,wulikuaicnt,zhuliucnt);
        }
    }
}


int main()
{
    int pagecnt;//定義頁面通路順序數組的長度
    int wulikuaicnt;//定義實體塊個數
    cout<<"input the number of page"<<endl;
    cin>>pagecnt;
    cout<<"input the number of block"<<endl;
    cin>>wulikuaicnt;

    int wulikuai[wulikuaicnt];//定義實體塊數組

    int zhuliucnt[wulikuaicnt];//用于記錄實體塊中各元素的滞留時間
    memset(wulikuai,-1,sizeof(wulikuai));//将實體塊中的所有元素先置為-1
    memset(zhuliucnt,0,sizeof(zhuliucnt));//将滞留時間數組全部置為0

    int i;
    int dangqianpage;//定義目前通路的頁面
    for(i=0;i<pagecnt;i++)
    {
        cout<<"input the rank of page"<<endl;
        cin>>dangqianpage;
        insertpage(dangqianpage,wulikuai,wulikuaicnt,zhuliucnt);
        cout<<"the situation of block"<<endl;
        dayinwulikuai(wulikuai,wulikuaicnt);
        for(int jj=0;jj<wulikuaicnt;jj++)
        {
            if(wulikuai[jj]!=-1)
            {
                zhuliucnt[jj]=zhuliucnt[jj]+1;
            }
        }
    }
    return 0;
}

           

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