c - Program runs then says it has stopped working. Debugging issues -

i writing code in c using codeblocks take schedule , tells if double booked on item.

the file setup like:

2 2 0 1 5 1 8 12 

where 1st number how many schedules there , second number how many scheduled items in schedule.

the next few lines read 0 sunday, 1 monday , forth , hours day schedule full, start time end time.

my code is:

//10/14/11 //this code functions let user know if schedule conflicts exist in amount of schedules.  #include <stdio.h>  int main() {     int hours_week[168];     int num_schedules;     int num_items;     int i;     int j;     int k;     int w;     file* ifp;     int day;     int start;     int end;     int schedule;     int booked;     int index;        //initialize array setting each spot equal zero.     (w=0; w<168; w++){         hours_week[w] = 0;     }      //read in file schedule.txt     ifp = fopen("schedule.txt","r");      //read in number of schedules     fscanf(ifp, "%d", &num_schedules);      //create loop run many times there schedules.     (i=0; i<num_schedules; i++){          //read in number of items in schedule.         fscanf(ifp, "%d", &num_items);          j = 0;         while (j < num_items){             j++;              //read in day, start time, , end time.             fscanf(ifp, "%d", day);             fscanf(ifp, "%d", start);             fscanf(ifp, "%d", end);              //multiply day 24 , add start , end hours new times.             start = (day * 24) + start;             end = (day * 24) + end;              (k = start; k <= end; k++){                 if (hours_week[k] == 0)                     hours_week[k] = 1;                 else if (hours_week[k] == 1)                     schedule = booked;             }              //close file             fclose(ifp);           if (schedule == booked)             printf("i'm sorry, schedule %d has conflict in it.\n", i);         else             printf("great planning! have no schedule conflicts in schedule %d.\n", i);         }     } return 0; } 

you miss address-of operator here

         //read in day, start time, , end time.         fscanf(ifp, "%d", day);         fscanf(ifp, "%d", start);         fscanf(ifp, "%d", end); 

correct should be

         //read in day, start time, , end time.         fscanf(ifp, "%d", &day);         fscanf(ifp, "%d", &start);         fscanf(ifp, "%d", &end); 

it's strange it's correct above! time go sleep, me @ least!