Add exercise

1 files changed, 43 insertions, 0 deletions

diff --git a/Year_3/Blockchain/RandomMoney.sol b/Year_3/Blockchain/RandomMoney.sol
new file mode 100644
index 0000000..2a5def4
--- /dev/null
+++ b/Year_3/Blockchain/RandomMoney.sol
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity >0.7 <0.9;
+
+contract RandomMoney {
+    uint public total;
+    uint public constant minFee = 10;
+    mapping(address => uint) public amounts;
+    address[] private members;
+
+
+    function play() public payable returns (uint) {
+        require(msg.value >= minFee, "Value is less than the required minimum");
+
+
+        amounts[msg.sender] += msg.value;
+
+        if (amounts[msg.sender] == msg.value) {
+            members.push(msg.sender);
+        }
+
+        total += msg.value;
+
+        return total;
+    }
+
+    function pay() public payable {
+        address payable account = payable(randomAddress());
+        account.transfer(total);
+        total = 0;
+    }
+
+    function randomAddress() internal view returns (address) {
+        uint8 num = uint8(
+            uint256(
+                keccak256(abi.encode(block.timestamp, block.difficulty))
+            ) % members.length
+        );
+
+        return members[num];
+    }
+}
+