c++ 可变分区存储管理模拟系统（FIFO,最优适应分配算法,最坏适应算法）

[c++]代码库
#include<stdio.h>
#include<iostream.h>
#include<string.h>
#include<iomanip.h>
 
const int MAXJOB=100;//定义表最大记录数
 
typedef struct node {
    int start;
    int length;
    char tag[20];
} job;
 
job frees[MAXJOB];//定义空闲区表
int free_quantity;
 
job occupys[MAXJOB];//定义已分配区表
int occupy_quantity;
 
//初始化函数
void initial() {
    int i;
 
    for ( i=0; i<MAXJOB; i++ ) {
        frees[i].start=-1;
        frees[i].length=0;
        strcpy ( frees[i].tag,"free" );
 
        occupys[i].start=-1;
        occupys[i].length=0;
        strcpy ( occupys[i].tag,"" );
    }
    free_quantity=0;
    occupy_quantity=0;
}
 
//读数据函数
int readData() {
    FILE *fp;
    char fname[20];
 
    cout<<"请输入初始空闲表文件名:";
    cin>>fname;
 
    if ( ( fp=fopen ( fname,"r" ) ) ==NULL ) {
        cout<<"错误,文件打不开,请检查文件名"<<endl;
    } else {
        while ( !feof ( fp ) ) {
            fscanf ( fp,"%d,%d",&frees[free_quantity].start,&frees[free_quantity].length );
            free_quantity++;
        }
        return 1;
    }
    return 0;
}
 
//sort
void sort() {
    int i,j,p;
 
    for ( i=0; i<free_quantity-1; i++ ) {
        p=i;
        for ( j=i+1; j<free_quantity; j++ ) {
            if ( frees[j].start<frees[p].start ) {
                p=j;
            }
        }
        if ( p!=i ) {
            frees[free_quantity]=frees[i];
            frees[i]=frees[p];
            frees[p]=frees[free_quantity];
        }
    }
}
 
 
//显示函数
void view() {
    int i;
 
    cout<<endl<<"----------------------------------------------------------"<<endl;
    cout<<"当前空闲表:"<<endl;
    cout<<"起始地址 长度 状态"<<endl;
    for ( i=0; i<free_quantity; i++ ) {
        cout.setf ( 2 );
        cout.width ( 12 );
        cout<<frees[i].start;
        cout.width ( 10 );
        cout<<frees[i].length;
        cout.width ( 8 );
        cout<<frees[i].tag<<endl;
    }
 
    cout<<endl<<"----------------------------------------------------------"<<endl;
    cout<<"当前已分配表:"<<endl;
    cout<<"起始地址 长度 占用作业名"<<endl;
    for ( i=0; i<occupy_quantity; i++ ) {
        cout.setf ( 2 );
        cout.width ( 12 );
        cout<<occupys[i].start;
        cout.width ( 10 );
        cout<<occupys[i].length;
        cout.width ( 8 );
        cout<<occupys[i].tag<<endl;
    }
}
 
//最先适应分配算法
void earliest() {
    char job_name[20];
    int job_length;
    int i,j,flag,t;
 
    cout<<"请输入新申请内存空间的作业名和空间大小:";
    cin>>job_name;
    cin>>job_length;
 
    flag=0;
    for ( i=0; i<free_quantity; i++ ) {
        if ( frees[i].length>=job_length ) {
            flag=1;
        }
    }
    if ( flag==0 ) {
        cout<<endl<<"Sorry,当前没有能满足你申请长度的空闲内存,请稍候再试"<<endl;
    } else {
        t=0;
        i=0;
        while ( t==0 ) {
            if ( frees[i].length>=job_length ) {
                t=1;
            }
            i++;
        }
        i--;
        occupys[occupy_quantity].start=frees[i].start;
        strcpy ( occupys[occupy_quantity].tag,job_name );
        occupys[occupy_quantity].length=job_length;
        occupy_quantity++;
 
        if ( frees[i].length>job_length ) {
            frees[i].start+=job_length;
            frees[i].length-=job_length;
        } else {
            for ( j=i; j<free_quantity-1; j++ ) {
                frees[j]=frees[j+1];
            }
            free_quantity--;
            cout<<"内存空间成功:)"<<endl;
        }
    }
}
//最优适应分配算法
void excellent() {
    char job_name[20];
    int job_length;
    int i,j,flag,t;
 
    cout<<"请输入新申请内存空间的作业名和空间大小:";
    cin>>job_name;
    cin>>job_length;
 
    flag=0;
    for ( i=0; i<free_quantity; i++ ) {
        if ( frees[i].length>=job_length ) {
            flag=1;
        }
    }
    if ( flag==0 ) {
        cout<<endl<<"Sorry,当前没有能满足你申请长度的空闲内存,请稍候再试"<<endl;
    } else {
        t=0;
        i=0;
        while ( t==0 ) {
            if ( frees[i].length>=job_length ) {
                t=1;
            }
            i++;
        }
        i--;
        for ( j=0; j<free_quantity; j++ ) {
            if ( ( frees[j].length>=job_length ) && ( frees[j].length<frees[i].length ) ) {
                i=j;
            }
        }
 
        occupys[occupy_quantity].start=frees[i].start;
        strcpy ( occupys[occupy_quantity].tag,job_name );
        occupys[occupy_quantity].length=job_length;
        occupy_quantity++;
 
        if ( frees[i].length>job_length ) {
            frees[i].start+=job_length;
            frees[i].length-=job_length;
        } else {
            for ( j=i; j<free_quantity-1; j++ ) {
                frees[j]=frees[j+1];
            }
            free_quantity--;
            cout<<"内存空间成功:)"<<endl;
        }
    }
}
 
//最坏适应算法
void worst() {
    char job_name[20];
    int job_length;
    int i,j,flag,t;
 
    cout<<"请输入新申请内存空间的作业名和空间大小:";
    cin>>job_name;
    cin>>job_length;
 
    flag=0;
    for ( i=0; i<free_quantity; i++ ) {
        if ( frees[i].length>=job_length ) {
            flag=1;
        }
    }
    if ( flag==0 ) {
        cout<<endl<<"Sorry,当前没有能满足你申请长度的空闲内存,请稍候再试"<<endl;
    } else {
        t=0;
        i=0;
        while ( t==0 ) {
            if ( frees[i].length>=job_length ) {
                t=1;
            }
            i++;
        }
        i--;
        for ( j=0; j<free_quantity; j++ ) {
            if ( ( frees[j].length>=job_length ) && ( frees[j].length>frees[i].length ) ) {
                i=j;
            }
        }
 
        occupys[occupy_quantity].start=frees[i].start;
        strcpy ( occupys[occupy_quantity].tag,job_name );
        occupys[occupy_quantity].length=job_length;
        occupy_quantity++;
 
        if ( frees[i].length>job_length ) {
            frees[i].start+=job_length;
            frees[i].length-=job_length;
        } else {
            for ( j=i; j<free_quantity-1; j++ ) {
                frees[j]=frees[j+1];
            }
            free_quantity--;
            cout<<"内存空间成功:)"<<endl;
        }
    }
}
 
//撤消作业
void finished() {
    char job_name[20];
    int i,j,flag,p=0;
    int start;
    int length;
 
    cout<<"请输入要撤消的作业名:";
    cin>>job_name;
 
    flag=-1;
    for ( i=0; i<occupy_quantity; i++ ) {
        if ( !strcmp ( occupys[i].tag,job_name ) ) {
            flag=i;
            start=occupys[i].start;
            length=occupys[i].length;
        }
    }
    if ( flag==-1 ) {
        cout<<"没有这个作业名"<<endl;
    } else {
//加入空闲表
        for ( i=0; i<free_quantity; i++ ) {
            if ( ( frees[i].start+frees[i].length ) ==start ) {
                if ( ( ( i+1 ) <free_quantity ) && ( frees[i+1].start==start+length ) ) {
                    frees[i].length=frees[i].length+frees[i+1].length+length;
                    for ( j=i+1; j<free_quantity; j++ ) {
                        frees[j]=frees[j+1];
                    }
                    free_quantity--;
                    p=1;
                } else {
                    frees[i].length+=length;
                    p=1;
                }
            }
            if ( frees[i].start== ( start+length ) ) {
                frees[i].start=start;
                frees[i].length+=length;
                p=1;
            }
        }
 
        if ( p==0 ) {
            frees[free_quantity].start=start;
            frees[free_quantity].length=length;
            free_quantity++;
        }
 
 
 
//删除分配表中的该作业
 
        for ( i=flag; i<occupy_quantity; i++ ) {
            occupys[i]=occupys[i+1];
        }
        occupy_quantity--;
    }
}
 
 
//显示版权信息函数
void version() {
    cout<<endl<<endl;
 
    cout<<" ┏━━━━━━━━━━━━━━━━━━━━━━━┓"<<endl;
    cout<<" ┃　　　 　可变分区存储管理模拟系统　 　　　　 ┃"<<endl;
    cout<<" ┠───────────────────────┨"<<endl;
    cout<<" ┃　 　(c)All Right Reserved Neo　　　 　　　┃"<<endl;
    cout<<" ┃　　　　　　sony006@163.com　　 　　　　　　　┃"<<endl;
    cout<<" ┃　　　　　version 2004 build 1122　　　　　　┃"<<endl;
    cout<<" ┗━━━━━━━━━━━━━━━━━━━━━━━┛"<<endl;
    cout<<endl<<endl;
}
 
 
void main() {
 
    int flag=0;
    int t=1;
    int chioce=0;
 
    version();
    initial();
 
    flag=readData();
 
    while ( flag==1 ) {
 
        sort();
        cout<<endl<<endl<<"========================================================="<<endl;
        cout<<" 可变分区存储管理模拟系统"<<endl;
        cout<<"========================================================="<<endl;
        cout<<" 1.申请空间 2.撤消作业 3.显示空闲表和分配表 0.退出"<<endl;
        cout<<"请选择:";
        cin>>chioce;
 
        switch ( chioce ) {
        case 1:
//换算法请换下一句调用
            earliest();
            break;
        case 2:
            finished();
            break;
        case 3:
            view();
            break;
        case 0:
            flag=0;
            break;
        default:
            cout<<"选择错误!"<<endl;
        }
    }
}