reading in file data

I'm new to c, and i've been given a project that requires me to read in data from files of varying length. i then put the data into an array and use it in some calculations. basically im having trouble with how to make the program realise these .txt files have different amounts of data in them and scan in only the appropriate amounts of information. is there a general way to read in file data without having to define how many pieces of data there are first? heres a section of my program where iv told the program the maximum number of bits of data, but this isn't working.
thanks

Code:

---


void filename()
{              /*entering the data from an existing file*/
char file[81];
puts("\nEnter the name of the file u wish to use\n");
scanf("%s", file);
path=fopen(file,"r");

fscanf(path, "%f%d%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f", &width, &steps, &y0, &y1, &y2, &y3, &y4, &y5, &y6, &y7, &y8, &y9, &y10, &y11, &y12, &y13, &y14, &y15, &y16, &y17, &y18, &y19, &y20, &y21, &y22, &y23, &y24, &y25, &y26, &y27, &y28, &y29, &y30);

printf("\nWidth of Beam = %fmm\n",width);
printf("\nNumber of steps = %d\n\n",steps);

calculations();
}
void calculations()
{ 
float array[33];
 
/*Putting data into an array*/
array[0] = width;
array[1] = steps;
array[2] = y0;
array[3] = y1;
array[4] = y2;
array[5] = y3;
array[6] = y4;   
array[7] = y5;
array[8] = y6;
array[9] = y7;
array[10] = y8;
array[11] = y9;
array[12] = y10;
array[13] = y11;
array[14] = y12;
array[15] = y13;
array[16] = y14;
array[17] = y15;   
array[18] = y16;
array[19] = y17;
array[20] = y18;
array[21] = y19;
array[22] = y20;
array[23] = y21;
array[24] = y22;
array[25] = y23;
array[26] = y24;
array[27] = y25;   
array[28] = y26;
array[29] = y27;
array[30] = y28;
array[31] = y29;
array[32] = y30;

---

You should be using a loop. Any why store into an array at the end? Why not just read right into the array from your fscanf()?

what sort of loop should i be looking at?can you give me an example, im really not understanding this bit of programming. i stored into an array because i need to then use some arithmetic to alter the array values then loop the new values into some further calculations
thanks