for (int n = 0; n <= 3; n++)
should rather read
for (int n = 0; n < 3; n++)
OLDvalues1[3] is a different variable and not part of your OLDvalues1[] array
This was not visible in your first post 
for (int n = 0; n <= 3; n++)
should rather read
for (int n = 0; n < 3; n++)
OLDvalues1[3] is a different variable and not part of your OLDvalues1[] array
This was not visible in your first post