What's the best way to fill multiDimensional Array

I am trying to find the best way to fill 2D Array with a specific value. Is there any better way to loop the 2D Array? I tried memset doesn't work I tried std::fill but I doubt there is something wrong with my code.

void fillMultipleArray(int m , int n , int value)

{ int grid[m][n] ;

memset(grid, 0, sizeof(grid));


for (int i = 0; i< m; i++) {
    
    for (int i = 0; i< n; i++) {
        
        std::cout<< grid[m][n]<< std::endl;
    }
}    

}

Output

-272632896 -272632896 -272632896 -272632896 -272632896 -272632896 -272632896 -272632896

Thanks in advance