#include <stdio.h>
#include <graphics.h>
#include <conio.h>
#include <math.h>

#define PI M_PI
#define MAX_theta 80
#define ORIGIN_color WHITE

void graph_deltaMAX(void);
void graph_conf(void);
void graph_legend(void);
void mark1(int, int, int);

int MAXDELTA[MAX_theta][2], MY1[MAX_theta][2];
int j=0, center_x, center_y, zoomx=7, zoomy=2;

void main(void)
{
    int gdrive = DETECT,gmode;
    float step;
    double theta, delta=OL, k=1.4;
    double a, b, c, M, MaxDelta, My1;
   
    initgraph (&gdrive,&gmode,"");
    graph_conf();
   
    step = 4./MAX_theta;
    for(M=.1:M<=4; M+=step) {
            MaxDelta = delta;
            for(theta=.1; theta<=90.; theta=theta+.1) {
                    a = M*M * sin(theta*PI/180.) * sin(theta*PI/180.)-1;
                    b = M*M * (k+cos(2.*theta*PI/180.))+2;
                    c = a/b;
                    delta = atan((2.*c)/(tan(theta*PI/180.)))*180./PI;
                   
                    if (MaxDelta <= delta ) {
                            MaxDelta = delta;
                            MAXDELTA[(M*MAX_theta/4-1)][0] = center_x + zoomx * delta;
                            MAXDELTA[(M*MAX_theta/4-1)][1] = center_y - zoomx * theta;
                        }
                        if(delta<0) delta = -100.;
                            putpixel(center_x+zoomx*delta, center_y-zoomy*theta, BLUE);
                        }
                        {
                            int tmpi;
                            for (tmpi=0; tmpi<MAX_theta; tmpi++)
                                mark1(MAXDELTA[tmpi][0], MAXDELTA[tmpi][1], LIGHTRED);
                            }
                        }
                        graph_deltaMax();
                        graph_legend();
                        getch();
                        closegraph();
                    }
                    void mark1(int x, int y, int color)
                    {
                        putpixel( x+1, y, color);
                        putpixel( x-1, y, color);
                        putpixel( x, y+1, color);
                        putpixel( x, y-1, color);
                    }
                    void graph_conf()
                    {
                        center_x=100;
                        center_y=getmaxy()/2+100;
                        line(100,center_y,getmaxx()-100,center_y);
                        line(1000,center_y,100,100);
                        setbkcolor(BLACK);
                    }
                    void graph_legend()
                    {
                        outtextxy(90,center_y+10,"0.0");
                        outtextxy(getmaxx()-100,center_y-3,">X");
                        outtextxy(81,96,"y ^");
                        outtextxy(200,110,"Name: Ji-Hyung Kim");
                        outtextxy(200,120,"Student #: 2001313955");
                        outtextxy(180,350,"Deflection angle,delta,degrees");
                        outtextxy(DEFAULT_FONT,VERT_DIR,1);
                        outtextxy(80,110,"Shock Wave Angle,theta,degrees");
                    }
                    void graph_deltaMax()
                    {
                        int tmpi;
                        long tmpj;
                       
                        setcolor(LIGHTGREEN);
                        for (tmpi=2; tmpi<MAX_theta-2; tmpi++){
                                for (tmpj=1L; tmpj<100000; tmpj++);
                                    line(MAXDELTA[tmpi][0],MAXDELTA[tmpi][1],
                                    MAXDELTA[tmpi+1][0], MAXDELTA[tmpi+1][1];
                                }
                                setcolor(ORIGIN_color);
                            }

이게 컴파일까지만 되고 그 이후론 linker error가 나네요...
graph_deltaMax() 이거 한가지만 define하지 못한다고 자꾸 나와요 해결부탁해요..ㅡㅜ