2 files changed, 5 insertions, 5 deletions
diff --git a/src/consensus/merkle.cpp b/src/consensus/merkle.cpp
index 1ce5a9d87e..798ce4b5fd 100644
--- a/src/consensus/merkle.cpp
+++ b/src/consensus/merkle.cpp
@@ -132,13 +132,13 @@ static void MerkleComputation(const std::vector<uint256>& leaves, uint256* proot
 
 uint256 ComputeMerkleRoot(const std::vector<uint256>& leaves, bool* mutated) {
     uint256 hash;
-    MerkleComputation(leaves, &hash, mutated, -1, NULL);
+    MerkleComputation(leaves, &hash, mutated, -1, nullptr);
     return hash;
 }
 
 std::vector<uint256> ComputeMerkleBranch(const std::vector<uint256>& leaves, uint32_t position) {
     std::vector<uint256> ret;
-    MerkleComputation(leaves, NULL, NULL, position, &ret);
+    MerkleComputation(leaves, nullptr, nullptr, position, &ret);
     return ret;
 }
 
diff --git a/src/consensus/merkle.h b/src/consensus/merkle.h
index 194aea9b75..33764c7460 100644
--- a/src/consensus/merkle.h
+++ b/src/consensus/merkle.h
@@ -12,7 +12,7 @@
 #include "primitives/block.h"
 #include "uint256.h"
 
-uint256 ComputeMerkleRoot(const std::vector<uint256>& leaves, bool* mutated = NULL);
+uint256 ComputeMerkleRoot(const std::vector<uint256>& leaves, bool* mutated = nullptr);
 std::vector<uint256> ComputeMerkleBranch(const std::vector<uint256>& leaves, uint32_t position);
 uint256 ComputeMerkleRootFromBranch(const uint256& leaf, const std::vector<uint256>& branch, uint32_t position);
 
@@ -20,13 +20,13 @@ uint256 ComputeMerkleRootFromBranch(const uint256& leaf, const std::vector<uint2
  * Compute the Merkle root of the transactions in a block.
  * *mutated is set to true if a duplicated subtree was found.
  */
-uint256 BlockMerkleRoot(const CBlock& block, bool* mutated = NULL);
+uint256 BlockMerkleRoot(const CBlock& block, bool* mutated = nullptr);
 
 /*
  * Compute the Merkle root of the witness transactions in a block.
  * *mutated is set to true if a duplicated subtree was found.
  */
-uint256 BlockWitnessMerkleRoot(const CBlock& block, bool* mutated = NULL);
+uint256 BlockWitnessMerkleRoot(const CBlock& block, bool* mutated = nullptr);
 
 /*
  * Compute the Merkle branch for the tree of transactions in a block, for a