C语言引用链接文件错误，编译错误

C语言编译错误，应该是没链接到对应文件，有人教教嘛
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<windows.h>
#include<mmsystem.h>
#pragma comment(lib, "Winmm.lib")

void play_music_1()
{
mciSendString("open music1.mp3 alias mymusic", NULL, 0, NULL);
mciSendString("play mymusic from 0 repeat", NULL, 0, NULL);
}

未定义-imp这一串字符

#include<string.h>
#include<stdlib.h>
#include <stdio.h>
#include <windows.h>
#include <mmsystem.h>

#pragma comment(lib, "Winmm.lib")

struct stu/定义学生类型/
{
long int carnum;
long int carword;
}stu[1000];

struct court/定义场地类型/
{
int courtnum;
int time[13];/0已预订，1未预订/
long int stunum;
}court[6]={{0,{0,0,1,1,1,1,0,0,0,0,1,1,1},0},{0,{1,1,0,0,0,0,1,1,1,1,0,0,1},0},{0,{1,1,1,1,0,0,0,0,0,0,0,0,0},0},{0,{0,0,1,1,1,1,0,0,0,0,0,1,1},0},{0,{0,0,1,1,1,1,0,0,0,0,0,1,1},0},{0,{0,0,0,0,1,1,1,0,0,1,1,0,0},0}};

void book();
void cancel();
void Exit();
void inquiry();
void printbook();
void printcourt();
void printfall();
void printtime();
void start();
void col();
void redcol();
void greencol();
void color();
void seat();
void play_music_1();

void col(char a[10])
{
HANDLE hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
SetConsoleTextAttribute(hConsole, FOREGROUND_INTENSITY | FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE | BACKGROUND_BLUE);
printf("%s",a);
}
void redcol(char a[10])
{
HANDLE hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
SetConsoleTextAttribute(hConsole, FOREGROUND_INTENSITY | FOREGROUND_RED | BACKGROUND_BLUE );
printf("%s",a);
}
void greencol(char a[10])
{
HANDLE hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
SetConsoleTextAttribute(hConsole, FOREGROUND_INTENSITY | FOREGROUND_GREEN | BACKGROUND_BLUE );
printf("%s",a);
}
void color(char a[10])
{
HANDLE hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
SetConsoleTextAttribute(hConsole, FOREGROUND_INTENSITY | FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE );
}

void seat(char c[30],char a[10],char b[10],char d[10],char e[10],char a1[10],int i,int j)
{
col(c);
redcol(a);
col(b);
printf(" are taken,");
greencol(d);
col(e);
printf(" are available\n");
printf("The court list is below:\n");
printf("┏━━━┳━━━┳━━━┳━━━┳━━━┓ \n");
printf("┃");printf("8-9\t");
printf("┃");printf("9-10 ");
printf("┃");printf("10-11 ");
printf("┃");printf("11-12 ");
printf("┃");printf("12-13 ");
printf("┃");
printf("\n┣━━━╋━━━╋━━━╋━━━╋━━━┫\n");
printf("┃");
for(j=0;j<5;j++){
if(court[i].time[j]==1){
a1="未预订";
redcol(a1);
printf("┃");
}
else{
a1="已预定";
greencol(a1);
printf("┃");
}
}

printf("\n┣━━━╋━━━╋━━━╋━━━╋━━━┫\n");
printf("┃");printf("13-14\t");
printf("┃");printf("14-15 ");
printf("┃");printf("15-16 ");
printf("┃");printf("16-17 ");
printf("┃");printf("17-18 ");
printf("┃"); 
printf("\n┣━━━╋━━━╋━━━╋━━━╋━━━┫\n");
printf("┃");
for(i=0,j=5;j<10;j++){
    if(court[i].time[j]==1){
        a1="未预订";
        redcol(a1);    
        printf("┃");
    }
    else{ 
        a1="已预定";
        greencol(a1);    
        printf("┃");
    }
}

printf("\n┣━━━╋━━━╋━━━╋━━━╋━━━┫\n");
printf("┃");printf("18-19\t");
printf("┃");printf("19-20 ");
printf("┃");printf("20-21");
printf(" ┃ ");
printf("     ┃");
printf("      ┃");    
printf("\n┣━━━╋━━━╋━━━╋━━━╋━━━┫\n");
printf("┃");
for(j=11;j<14;j++){
    if(court[i].time[j]==1){
        a1="已预订";
        redcol(a1);
        printf("┃");
    }
    else{ 
        a1="未预定";
        greencol(a1);
        printf("┃");
    }
}
printf("      ┃");
printf("      ┃");

printf("\n┗━━━┻━━━┻━━━┻━━━┻━━━┛\n");
getchar();

}

void play_music_1()
{
mciSendString("open music1.mp3 alias mymusic", NULL, 0, NULL);
mciSendString("play mymusic from 0 repeat", NULL, 0, NULL);
}

int main(void)
{
int i;
char c;
system("color 37");
/*mciSendstring("open"music.mp3"alias file",NULL,0,NULL);
//micSendString("play file",NULL,NULL);
//getchar();
//Sleep(60 1000);/
printf("\n");
printf("欢迎进入体育馆预约系统！");
play_music_1();
Sleep(10000); //播放时间 1000=1s//
//close_music();
getchar();
system("CLS");
while(1){
printf("\t\t\t1.查询空场地\n\t\t\t2.预约场地\n\t\t\t3.取消预定\n\t\t\t4.历史预约查询\n\t\t\t0.退出\n");
scanf("%d",&i);
system("CLS");
switch(i){
case 1:inquiry();break;
case 2:book();break;
case 3:cancel();break;
case 4:printfall();break;
case 0:Exit(0);
default:printf("error\n");
}
}

}

void Exit()
{
getchar();
printf("\t\n");
printf("\n\n\t\t\t谢谢您的使用!\n");
printf("\n\t\t 欢迎下次使用!\n\n");
printf("\t\n");
printf("\n");
getchar();
}

void printfall()
{

int i,j;
printf("----------------------------输出全部场地信息------------------------------------\n");
printf("√为已预订，×为未预定\n");

printf("场地号\t");
printf("8-9\t9-10\t10-11\t11-12\t12-13\t13-14\t14-15\n");
for(i=0;i<6;i++){
    printf(" %d\t",i+1);
    for(j=0;j<7;j++){
        if(court[i].time[j]==1)
            printf("√\t");
        else
            printf("×\t");
    }
    printf("\n");
}
printf("15-16\t16-17\t17-18\t18-19\t19-20\t20-21\n");
for(i=0;i<6;i++){
    printf(" %d\t",i+1);
    for(j=7;j<13;j++){
        if(court[i].time[j]==1)
            printf("√\t");
        else
            printf("×\t");
    }
    printf("\n");
}
getchar();
getchar();
system("CLS");

}

void inquiry()
{
int i;
printf("\t\t1.按场地号显示场地预定情况\t\n\t\t2.按时间段显示场地预定情况\t\n");
scanf("%d",&i);
switch(i){
case 1:printcourt();break;
case 2:printtime();break;
default:printf("error\n");
}
}

void printcourt()/*按场地号显示场地预定情况 */
{

int number;
char s;
char c[30]="Choose your seat please\n",a[10]=" red ",b[10]="ones",d[10]="green",e[10]=" ones";
char a1[10];
printf("----------------------------按场地号查询----------------------------------------\n");

printf("\t\t请输入要预定的场地号\t\n");
do{
    printf("\t请输入:\t");
    scanf("%d",&number);
    printf("^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n");
    printf("\t\t\t***%d号地的预定情况***\n",number);

    seat(c,a,b,d,e,a1,number,13);

    system("color 37");
    printf("\n^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^");
    printf("\n继续查询请输入y，返回请输入n。\n");
    scanf("%s",&s);    
    getchar();
    system("CLS");

}while(s=='y');

}

void printtime()/按时间段显示场地预定情况/
{

int i,j,t1,t2,a;
char s;

do{
    printf("----------------------------------按时间段查询-------------------------------------\n");
    printf("\t\t请输入要查询的时间段\t\n\t\t例如 10,11(用逗号隔开)\n");
    printf("\t请输入:");
    scanf("%d,%d",&t1,&t2);
    a=t2-t1;
    printf("\n^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n");
    printf("-----------------------------%d-%d时间段可预订的场地号:-------------------------\n",t1,t2);
    for(i=0;i<6;i++){
        for(j=t1-8;j<t2-8;j++)
            if(court[i].time[j]==1)
                break;
        if(j==t2-8)
                printf("%d号\t",i+1);
    }
    printf("\n^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n");
    printf("\n<继续查询>输入y\t<返回>输入n.\n");
    scanf("%s",&s);
}while(s=='y');
system("CLS");

}

void book()
{
FILE*fp,*fp1;
int i,j,k,t1,t2;
char x='0',y;
int number,cardnum,cardword;
printf("----------------------------------选择要预定的场地------------------------------\n");
if((fp=fopen("student.txt","r+"))==NULL){
printf("不能打开student文件\n");
exit(0);
}
for(i=0;i<40;i++)
fscanf(fp,"%9d\t%9d\t",&stu[i].carnum,&stu[i].carword);
printf("\n");
fclose(fp);

printf("\t\t请输入卡号:\t");
scanf("%d",&cardnum);
printf("\t\t请输入密码:\t");
scanf("%d",&cardword);

for(i=0;i<40;i++){
    if(stu[i].carnum==cardnum&&stu[i].carword==cardword){
        do{
            do{
                printf("\t\t请输入要预定的场地号:\t");
                scanf("%d",&number);
                if(number>6||number<1){
                    x='1';
                    printf("输入有误!请重试!\n");
                }
            }while(x=='1');
            do{
                printf("\t\t请输入要预定的时间段:\n\t\t例如\t10,11(用逗号隔开)\n\t\t");
                scanf("%d,%d",&t1,&t2);
                if(t1>t2||(t1<8||t2>21)){
                    printf("\t\t输入有误!请重试!\n");
                    x='2';
                }
            }while(x=='2');
            for(j=t1-8;j<t2-8;j++)
                if(court[number-1].time[j]==1)
                    break;
            if(j==t2-8){
                for(k=t1-8;k<t2-8;k++){
                    court[number-1].time[k]=1;
                    court[number-1].stunum=cardnum;
                }
                printf("\t\t预定成功！\n\t\t场地号是%d,时间是%d-%d你的学号是%ld\n",number,t1,t2,court[number-1].stunum);
                printf("\t\t1.<继续预定>\t0.<返回>\n\t\t");
                scanf("%s",&y);
            }
            else{
                printf("\t\t该场地该时间段被预订，抱歉！\n\t\t重新选择场地请输入y;返回请输入n.\n\t\t");
                scanf("%s",&y);
            }
        }while(y=='1');
        break;
    }
}
if(i==40){
    printf("\t\t您输入的卡号或密码错误，请重试！\n");
    printf("\t\t按任意键返回\n");
    getchar();
}
getchar();
system("CLS");

}

void cancel()
{
FILE*fp,*fp1;
int i,j,m=0,t1,t2;
int max,counum,cardnum,cardword;
char x='0',y;
char ture='0';
printf("----------------------------------取消预定--------------------------------------\n");
if((fp=fopen("student.txt","r+"))==NULL){
printf("不能打开student文件\n");
exit(0);
}
for(i=0;i<40;i++)
fscanf(fp,"%9d\t%9d\t",&stu[i].carnum,&stu[i].carword);
printf("\n");
max=i;
fclose(fp);

printf("\t\t请输入卡号:\t");
scanf("%d",&cardnum);
printf("\t\t请输入密码:\t");
scanf("%d",&cardword);

for(i=0;i<max;i++){
    if(stu[i].carnum==cardnum&&stu[i].carword==cardword){
        do{
            do{
                printf("\t\t请输入要取消的场地号:\t");
                scanf("%d",&counum);
                if(counum>6||counum<1){
                    x='1';
                    printf("输入有误!请重试!\n");
                }
            }while(x=='1');
            do{
                printf("\t\t请输入要取消的时间段:\n\t\t例如\t10,11(用逗号隔开)\n\t\t");
                scanf("%d,%d",&t1,&t2);
                if(t1>t2||(t1<8||t2>21)){
                    printf("\t\t输入有误!请重试!\n");
                    x='2';
                }
            }while(x=='2');

            for(j=t1-8;j<t2-8;j++)
            if(court[counum-1].time[j]==0)
                break;
            if(j==t2-8){
                for(j=t1-8;j<t2-8;j++){
                    court[counum-1].stunum=0;
                    court[counum-1].time[j]=0;
                }
                printf("\t\t退场成功!\n");
                printf("\t\t1.<继续退场>\t0.<返回>\n\t\t");
                scanf("%s",&y);
            }
            else{
                printf("\t\t该场地该时间段没有预订！\n\t\t重新选择场地请输入y;返回请输入n.\n\t\t");
                scanf("%s",&y);
            }
        }while(y=='1');
        break;
    }
}
if(i==max){
    printf("\t\t您输入的卡号或密码错误，请重试！\n");
    printf("\t\t按任意键返回\n");
    getchar();
}
getchar();
system("CLS");

}