Thread: pls help me in this error...urgent

L111 : invalid types for array subscript

Code:

#include <stdio.h>
#include <time.h>
#include <math.h>
#include <stdlib.h>

typedef struct {
     int x;
	 int y;
	 }city;
	 
permute(city *a,int n,int t,int **d,int *b)
{ 
  int i,j,temp1,temp2;
  
  if(n==1)
   {
     for(j=0;j<t-1;j++)
	   (*b) += d[j][j+1];
	 (*b) += d[j][0];
	 b++;
	 }
	 
  else
    {
     for(i=1;i<n;i++)
      {	
        temp1 = (a+i)->x;
		temp2 = (a+i)->y;
        (a+i)->x = (a+(n-1))->x;
		(a+i)->y = (a+(n-1))->y;
	    (a+(n-1))->x = temp1;
		(a+(n-1))->y = temp2;
		
	    permute(a,n-1,t,d,b);
		
	    temp1 = (a+i)->x;
		temp2 = (a+i)->y;
        (a+i)->x = (a+(n-1))->x;
		(a+i)->y = (a+(n-1))->y;
	    (a+(n-1))->x = temp1;
		(a+(n-1))->y = temp2;
      }  
   }
   
}

minimum(int *b, int n)
{ 
  int min;
  for(int i=n-2;i<=0;i++)
     if(*(b+i)<min)
	   min = *(b+i);
  printf("Minimum cost for the trip is %d\n\n",min); 
}

int main()
{
int n;
printf("How many cities you want to travel (include the starting position ,too, in your number)\n\n");
scanf("%d",&n);
city *a;
a=(city *)malloc(n*sizeof(city));
printf("\n\nAssume the x and y co-ordinate of the city from where you start(or end) the journey to be (0,0)\n\n");
a->x=0;
a->y=0;
printf("Data stored for the city from where you start\n\n");
printf("Now ,storing x and y co-ordinate of the other cities (random value)\n\n");
printf("press enter to randomly generate the co-ordinates.....");
srand((unsigned)time ( NULL ) );
for(int i=1;i<n;i++)
{
(a+i)->x= 0 + rand()%1000;
(a+i)->y= 0 + rand()%1000;
}
printf("\n\nData storing successful for other cities\n\n");
printf("Now, sorting the cities with respect to their x co-ordinates\n\n");
printf("press enter to sort the cities......");
int temp1,temp2;
for(int j=0;j<n-1;j++)
  for(int k=j+1;k<n;k++)
    {
	  if((a+j)->x > (a+k)->x)
	   {
		 temp1 = (a+j)->x;
		 temp2 = (a+j)->y;
		 (a+j)->x = (a+k)->x;
		 (a+j)->y = (a+k)->y;
		 (a+k)->x = temp1;
		 (a+k)->y = temp2;
		}
	}
printf("\n\ncities with respect to their x co-ordinate is sorted\n\n");
int d[n][n];
printf("calculating the distance between the cities\n\n");
printf("press enter to calculate and store.....");
int m,l,g;
for(l=0;l<n-1;l++)
  for(m=l;m<n;m++)
     d[l][m] = (int) sqrt(pow(((a+l)->x - (a+m)->x),2) + pow(((a+l)->y - (a+m)->y),2));
for(l=1;l<n;l++)
  for(m=0;m<l;m++)
     d[l][m] = d[m][l];
printf("\n\nDistances calculated and stored\n\n");
int fac,min;
fac = 1;
for(g=1;g<=n-1;g++)
   fac *= g;
fac +=1;
int *b;
b =(int *)malloc(fac*sizeof(int));
permute[a,n,n,d,b];
minimum[b,fac];  
}

And on which line of all that code is the error occuring?

Your compiler's error messages should contain a line number so you can go directly to the offending line....

Also you should turn your compiler's error and warning levels up to maximum and whatever it prints out should be seen as a problem to be corrected.

Yes... compiler errors are your friends...