echo Test 1.  Should print 3424505894 913236
./pamenlarge 3 ../testimg.ppm | cksum
echo Test 2.  Should print 4152147096 304422
ppmtopgm ../testimg.ppm | ./pamenlarge 3 | cksum
echo Test 3.  Should print 3342398172 297
./pamenlarge 3 ../testgrid.pbm | cksum
echo Test 4.  Should print 237488670 3133413
./pamenlarge 3 -plain ../testimg.ppm | cksum