animation not working correctly

it is a very simple code in which length of lines is changed by comparing with a data in vector. Here is the code:

using namespace std;
ifstream fin(“testanim.txt”);

double x,y,z;

struct point
{
double x,y,z;
};

vector<point> temp;

void ReadTp(int)
{
if(!fin.eof())
{

	double x,y,z;
	fin&gt;&gt;x&gt;&gt;y&gt;&gt;z;
	point hold={x,y,z};
	temp.push_back(hold);
}


glClear(GL_COLOR_BUFFER_BIT);
glutTimerFunc(100, ReadTp,1);
glutPostRedisplay();

}

void reshape (int w, int h)
{
glViewport (0, 0, (GLsizei) w, (GLsizei) h);
glMatrixMode (GL_PROJECTION);
glLoadIdentity ();
glOrtho(-35,35,-35,35,-20,20);

}

void display()
{

glClear(GL_COLOR_BUFFER_BIT);	
glColor3f(1,0,0);
glMatrixMode (GL_MODELVIEW);
glLoadIdentity();
glRotatef(-90, 1.0f, 0.0f, 0.0f);
glRotatef(xrot, 1.0f, 0.0f, 0.0f);
glRotatef(yrot, 0.0f, 1.0f, 0.0f);

double tt=10;
glBegin(GL_LINES);

  for(float i=0;i&lt;20;i=i+1)
  {
	 
	tt=12;
	for(int k=0;k&lt;temp.size();k++)
	{

	if(i==temp[k].x)
	 {
		 tt=temp[k].z;
	 }

	}
	  glVertex3f(i,0,0);
	  glVertex3f(i,0,tt);
  }

  
  glEnd();
  glutSwapBuffers();

}

void initialize(int argc, char* argv[])
{
glutInit(&argc,argv);
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH);
glutInitWindowSize(500,500);
glutInitWindowPosition(100,101);
glutCreateWindow(“try”);
glClearColor(1,1,1,0.3);
glutDisplayFunc(display);
glutTimerFunc(0,ReadTp,1);

glutReshapeFunc(reshape);
glutMainLoop();

}
void main(int argc, char* argv[])
{
double j,k,l;

for(int i=0;i&lt;100;i++)
{
fin&gt;&gt;j&gt;&gt;k&gt;&gt;l;
point tempo={j,k,l};
temp.push_back(tempo);
}
initialize(argc,argv);

}

But the height of some of the first lines does not change by animation(i.e. one by one) but displays instantly. and the next lines change length one by one giving a animation

I am using glut in vc++ 2010.

The file testanim has the following data:
0 0 9
1 0 8
2 0 7
3 0 6
4 0 5
5 0 4
6 0 5
7 0 6
8 0 7
9 0 8
10 0 9
11 0 8
12 0 7
13 0 6
14 0 5
15 0 4
16 0 5
17 0 6
18 0 7
19 0 8

[QUOTE=qawded;1252518]it is a very simple code in which length of lines is changed by comparing with a data in vector. Here is the code:

SOMEONE PLEASE HELP.