btw this is a part of a battleship code

i want to know what the integers a,b,c,d,e,f... do

I know this has something to do with placing ships randomly but it is a little complexed for me. I'd appreciate it if someone took their time to explain it

```
int placeship( int x, int z[ ][ 10 ] )
{
int a, b, c, d, e, f, g, h, i, j, k;
int pc;
int usum, dsum, lsum, rsum;
usum = 0;
dsum = 0;
lsum = 0;
rsum = 0;
pc = 0;
a = rand() % 10;
b = rand() % 10;
c = rand() % 2;
f = a + x;
g = b + x;
e = (x - 1);
for( d = 0; d <= e; d++)
{
i = a - d;
if( z[ i ][ b ] == 1 )
{
usum++;
}
}
for( d = 0; d <= e; d++)
{
j = a + d;
if( z[ j ][ b ] == 1 )
{
dsum++;
}
}
for( d = 0; d <= e; d++)
{
k = b - d;
if( z[ a ][ k ] == 1 )
{
lsum++;
}
}
for( d = 0; d <= e; d++)
{
h = b + d;
if( z[ a ][ h ] == 1 )
{
rsum++;
}
}
if( c != 1 ) // vector: U/D
{
if( f >= 10 )
{
if( usum == 0 )
{
for( d = 0; d <= e; d++) // vector: up ^
{
i = a - d;
z[ i ][ b ] = 1;
}
pc = 1;
}
}
if( f < 10 )
{
if( dsum == 0)
{
for( d = 0; d <= e; d++) // vector: down v
{
j = a + d;
z[ j ][ b ] = 1;
}
pc = 1;
}
}
}
if( c == 1 ) // vector: L/R
{
if( g >= 10 )
{
if( lsum == 0 )
{
for( d = 0; d <= e; d++) // vector: left <-
{
k = b - d;
z[ a ][ k ] = 1;
}
pc = 1;
}
}
if( g < 10 )
{
if( rsum == 0 )
{
for( d = 0; d <= e; d++) // vector: right ->
{
h = b + d;
z[ a ][ h ] = 1;
}
pc = 1;
}
}
}
return pc;
```