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OverflowandUnderflow.sol

pragma solidity ^0.4.24;

contract OverflowandUnderflow{
    function overflow() public pure returns(uint256){
        uint256 max=2**256-1;
        return max+1;
    }
    
     function underflow() public pure returns(uint256){
        uint256 min=0;
        return min-1;
    }
}