If / Else

Solidity support conditional statements if, else if and else.

// SPDX-License-Identifier: MIT
pragma solidity ^0.6.10;

contract IfElse {
    function foo(uint x) public pure returns (uint) {
        if (x < 10) {
            return 0;
        } else if (x < 20) {
            return 1;
        } else {
            return 2;
        }
    }
}

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