So here is my code:
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#define MAX n
int t,n;
int readtime ();
int readboardsize();
void readboard(int board[MAX][MAX], int n);
void printboard(int board[MAX][MAX]);
int main(int argc, char * argv[]){
int board[MAX][MAX];
t = readtime();
n = readboardsize();
printf("%d\n",n);
readboard(board,n);
printboard(board);
return 0;
}
int readtime() {
int nvr, scannedt;
printf("Enter t :");
nvr = scanf("%d",&scannedt);
if (scannedt>1000 || scannedt<0 || nvr==0) {
printf("Incorrect input: t must be 0..1000\n");
exit(EXIT_FAILURE);
}
return scannedt;
}
int readboardsize() {
int nvr,scannedn;
printf("Enter n :");
nvr = scanf("%d",&scannedn);
if (scannedn>25 || scannedn<3) {
printf("Incorrect input: n must be 3..25\n");
exit(EXIT_FAILURE);
}
return scannedn;
}
void readboard(int board[MAX][MAX], int n) {
int i,j,nvr;
printf("Enter %d by %d forrest:\n",n,n);
for(i = 0; i < MAX; i++){
for(j=0; j < MAX; j++){
nvr = scanf("%d",&board[i][j]);
}
}
}
void printboard(int board[MAX][MAX]) {
int i,j;
printf("Here is the board:\n\n");
for(i = 0; i < MAX; i++){
for(j=0; j < MAX; j++){
if (board[i][j]==0 ) {
printf(". ");
}else if (board[i][j]==1){
printf("^ ");
}else if (board[i][j]==2){
printf("* ");
}
}
printf("\n");
}
}
When I compile it, it completes successfully but after I input the array I get this error:
*** stack smashing detected ***: ./ass2 terminated
======= Backtrace: =========
/lib/libc.so.6(__fortify_fail+0x50)[0x3e3990]
/lib/libc.so.6(+0xe593a)[0x3e393a]
./ass2[0x8048768]
/lib/libc.so.6(__libc_start_main+0xe7)[0x314ce7]
./ass2[0x8048421]
======= Memory map: ========
00110000-0012a000 r-xp 00000000 08:01 129968 /lib/libgcc_s.so.1
0012a000-0012b000 r--p 00019000 08:01 129968 /lib/libgcc_s.so.1
0012b000-0012c000 rw-p 0001a000 08:01 129968 /lib/libgcc_s.so.1
0025e000-0025f000 r-xp 00000000 00:00 0 [vdso]
002fe000-00455000 r-xp 00000开发者_JS百科000 08:01 134635 /lib/libc-2.12.1.so
00455000-00456000 ---p 00157000 08:01 134635 /lib/libc-2.12.1.so
00456000-00458000 r--p 00157000 08:01 134635 /lib/libc-2.12.1.so
00458000-00459000 rw-p 00159000 08:01 134635 /lib/libc-2.12.1.so
00459000-0045c000 rw-p 00000000 00:00 0
00c1f000-00c3b000 r-xp 00000000 08:01 130134 /lib/ld-2.12.1.so
00c3b000-00c3c000 r--p 0001b000 08:01 130134 /lib/ld-2.12.1.so
00c3c000-00c3d000 rw-p 0001c000 08:01 130134 /lib/ld-2.12.1.so
08048000-08049000 r-xp 00000000 08:01 427835 /home/stu/Work/comp1911/ass2/ass2
08049000-0804a000 r--p 00000000 08:01 427835 /home/stu/Work/comp1911/ass2/ass2
0804a000-0804b000 rw-p 00001000 08:01 427835 /home/stu/Work/comp1911/ass2/ass2
09c12000-09c33000 rw-p 00000000 00:00 0 [heap]
b7830000-b7831000 rw-p 00000000 00:00 0
b783e000-b7842000 rw-p 00000000 00:00 0
bfe46000-bfe67000 rw-p 00000000 00:00 0 [stack]
Aborted
Can anyone give me a hand with whats going on?
Kind Regards
Dennis
You #define MAX n
and then int n;
just below that. So, n
will be initialized to zero as it has file scope (someone correct me on this if I'm wrong please, I checked a few examples but that's no guarantee and I don't have a copy of the standard handy). Then you have this in main:
int board[MAX][MAX];
And then a little bit later you finally assign a value to n
and then proceed to use that. But, your board
was created using the initial value of n
. The result is that everything is assuming that board
is bigger than it really is and that's how you smash your stack.
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