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stack.sol

pragma solidity ^0.5.1;

contract Stack {
    int256[] stack;

    function push(int256 data) public {
        stack.push(data);
    }

    function pop() public returns (int256 data) {
        data = stack[stack.length - 1];

        stack.length -= 1;
    }
    
    function incTop() public {
        int256 data = pop();
        data += 28;
        push(data);
    }
}