main() {
	assert 0 - 0 == 0
	assert 0 - 1 == -1
	assert 0 - -1 == 1
	assert 1 - 0 == 1
	assert 1 - 1 == 0
	assert 1 - -1 == 2
	assert 2 - 2 == 0
	assert 4 - 4 == 0
	assert 8 - 8 == 0
	assert 16 - 16 == 0
	assert 32 - 32 == 0
	assert 64 - 64 == 0
	assert 128 - 128 == 0
	assert 256 - 256 == 0
	assert 512 - 512 == 0
	assert 1024 - 1024 == 0
	assert 2048 - 2048 == 0
	assert 4096 - 4096 == 0
	assert 8192 - 8192 == 0
	assert 16384 - 16384 == 0
	assert 32768 - 32768 == 0
	assert 65536 - 65536 == 0
	assert 131072 - 131072 == 0
	assert 262144 - 262144 == 0
	assert 524288 - 524288 == 0
	assert 1048576 - 1048576 == 0
	assert 2097152 - 2097152 == 0
	assert 4194304 - 4194304 == 0
	assert 8388608 - 8388608 == 0
	assert 16777216 - 16777216 == 0
	assert 33554432 - 33554432 == 0
	assert 67108864 - 67108864 == 0
	assert 134217728 - 134217728 == 0
	assert 268435456 - 268435456 == 0
	assert 536870912 - 536870912 == 0
	assert 1073741824 - 1073741824 == 0
	assert 2147483648 - 2147483648 == 0
	assert 4294967296 - 4294967296 == 0
	assert 8589934592 - 8589934592 == 0
	assert 17179869184 - 17179869184 == 0
	assert 34359738368 - 34359738368 == 0
	assert 68719476736 - 68719476736 == 0
	assert 137438953472 - 137438953472 == 0
	assert 274877906944 - 274877906944 == 0
	assert 549755813888 - 549755813888 == 0
	assert 1099511627776 - 1099511627776 == 0
	assert 2199023255552 - 2199023255552 == 0
	assert 4398046511104 - 4398046511104 == 0
	assert 8796093022208 - 8796093022208 == 0
	assert 17592186044416 - 17592186044416 == 0
	assert 35184372088832 - 35184372088832 == 0
	assert 70368744177664 - 70368744177664 == 0
	assert 140737488355328 - 140737488355328 == 0
	assert 281474976710656 - 281474976710656 == 0
	assert 562949953421312 - 562949953421312 == 0
	assert 1125899906842624 - 1125899906842624 == 0
	assert 2251799813685248 - 2251799813685248 == 0
	assert 4503599627370496 - 4503599627370496 == 0
	assert 9007199254740992 - 9007199254740992 == 0
	assert 18014398509481984 - 18014398509481984 == 0
	assert 36028797018963968 - 36028797018963968 == 0
	assert 72057594037927936 - 72057594037927936 == 0
	assert 144115188075855872 - 144115188075855872 == 0
	assert 288230376151711744 - 288230376151711744 == 0
	assert 576460752303423488 - 576460752303423488 == 0
	assert 1152921504606846976 - 1152921504606846976 == 0
	assert 2305843009213693952 - 2305843009213693952 == 0
}