contract C {
    bytes32 constant a = keccak256(abi.encode(1, 2));
    bytes32 constant b = keccak256(abi.encodePacked(uint(1), a));
    bytes32 constant c = keccak256(abi.encodeWithSelector(0x12345678, b, 2));
    bytes32 constant d = keccak256(abi.encodeWithSignature("f()", 1, 2));
}
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