scanf() causing segmentation fault when previously working fine [closed] - c

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I'm currently programming a version of Conway's Game of Life in C as part of an assignment for my degree course. Within the code, I ask the user to enter an integer representing a menu item describing the game's initial conditions.
When I tested the code surrounding this on it's own, it worked fine, scanning in the values correctly and printing them out fine etc.
However, I have now continued with my code and begun developing the next stage and now suddenly I am getting a segmentation fault which, using printf, I pinpointed back to this very same previously working scanf statement.
Is anyone able to point me in the direction of why this scanf is suddenly giving such a fault, so I can hence address the problem.
My code is as follows:
#include <stdio.h>
#include <math.h>
#include <string.h>
#define WIDTH 60
#define HEIGHT 60
#define NAMELENGTH 128
void initGrid(int choice, int grid[][WIDTH]){
int a,b;
for(a=0;a<HEIGHT;++a){
for(b=0;a<WIDTH;++b){
grid[a][b]=0;
}
}
switch(choice){
case 1 :
grid[6][3]=1;
grid[7][3]=1;
grid[6][4]=1;
grid[7][4]=1;
grid[6][13]=1;
grid[7][13]=1;
grid[8][13]=1;
grid[5][14]=1;
grid[4][15]=1;
grid[4][16]=1;
grid[9][14]=1;
grid[10][15]=1;
grid[10][16]=1;
grid[7][17]=1;
grid[5][18]=1;
grid[9][18]=1;
grid[6][19]=1;
grid[7][19]=1;
grid[8][19]=1;
grid[7][20]=1;
grid[4][23]=1;
grid[5][23]=1;
grid[6][23]=1;
grid[4][24]=1;
grid[5][24]=1;
grid[6][24]=1;
grid[3][25]=1;
grid[7][25]=1;
grid[2][27]=1;
grid[3][27]=1;
grid[7][27]=1;
grid[8][27]=1;
grid[4][37]=1;
grid[5][37]=1;
grid[4][38]=1;
grid[5][38]=1;
break;
case 2 :
grid[29][29]=1;
grid[28][29]=1;
grid[30][29]=1;
grid[29][28]=1;
grid[28][30]=1;
break;
default :
break;
}
}
int main() {
int currGrid[HEIGHT][WIDTH];
//int nextGrid[HEIGHT][WIDTH];
char name[NAMELENGTH];
printf("Welcome to Conway's Game of Life. To Begin, What Is Your Name?\n");
scanf("%[^\n]%*c", name);
int menSelect;
printf("Hello %s, Please Enter the Integer Next to the Item Below That Describes How You Would Like Your Game of Life to Initially Be Set Up\n \n 1. Gosper's Glider Gun \n 2. R-Pentomino\n ", name);
for(;;){
int checkIn=scanf("%d",&menSelect);
if(checkIn!=1){
fprintf(stderr,"Scanf Has Failed to Read In Any Values\n");
}
if(menSelect!=1 && menSelect!=2){
fprintf(stderr,"%s, %d Is Not a Valid Selection\nPlease Try Again\n",name,menSelect);
}else{
break;
}
}
initGrid(menSelect,currGrid);
return 1;
}
The offending line is int checkIn=scanf("%d",&menSelect); from what I can tell but I can't figure out why.
Many thanks

Answer 1

Undefined behaviour because of how you zero the grid. Looks like a copy/paste error.
for(b=0;a<WIDTH;++b){
^^^
You meant b < WIDTH.