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contracts/lib/DecimalMath.sol

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+/*
+
+    Copyright 2020 DODO ZOO.
+    SPDX-License-Identifier: Apache-2.0
+
+*/
+
+pragma solidity 0.6.9;
+pragma experimental ABIEncoderV2;
+
+import {SafeMath} from "./SafeMath.sol";
+
+/**
+ * @title DecimalMath
+ * @author DODO Breeder
+ *
+ * @notice Functions for fixed point number with 18 decimals
+ */
+library DecimalMath {
+    using SafeMath for uint256;
+
+    uint256 constant ONE = 10**18;
+
+    function mul(uint256 target, uint256 d) internal pure returns (uint256) {
+        return target.mul(d) / ONE;
+    }
+
+    function divFloor(uint256 target, uint256 d) internal pure returns (uint256) {
+        return target.mul(ONE).div(d);
+    }
+
+    function divCeil(uint256 target, uint256 d) internal pure returns (uint256) {
+        return target.mul(ONE).divCeil(d);
+    }
+}