Matrix that makes use of an struct - c

Question

I have a matrix, and a struct with 2 int variables.
struct virus {
int gen;
int neighbours;
}
I want to initialize my full gen matrix with the 1 value. The problem is it doesn't work for the first column of the matrix.
I'll post down bellow the code.
Also when I tried to set my matrix as the virus struct it didn't work and I had to initialize a new matrix that I called b.
It's just a simple initialization and a printing.
#include <stdio.h>
struct virus {
int gen;
int neighbours;
};
void initGen(int n, int a[][100])
{
struct virus b[n][100];
int i,j;
for(i = 0; i < n; i++)
{
for(j = 0; j < n; j++)
{
b[i][j].gen = 1;
}
}
}
void printMatrixGen(int n, int b[][100])
{
struct virus a[n][100];
int i;
for(i = 0; i < n; i++)
{
int j;
for(j = 0; j < n; j++)
printf("%d\t", a[i][j].gen);
printf("\n");
}
}
int main(void)
{
int a[100][100], n;
n = 4;
initGen(n,a);
printMatrixGen(n,a);
return 0;
}
The output is the matrix
0 1 1 1
0 1 1 1
0 1 1 1
0 1 1 1
Instead of
1 1 1 1
1 1 1 1
1 1 1 1
1 1 1 1

Answer 1

Your code passes a wrong array. You need to change function signatures as follows:
void initGen(int n, struct virus a[][100]);
void printMatrixGen(int n, struct virus a[][100]);
After that, remove local declaration of struct virus b arrays, and use structs passed as parameters.
Finally, declare your struct array inside main, and pass it to both functions:
struct virus a[100][100];
int n = 4;
initGen(n, a);
printMatrixGen(n, a);