Added merkleTreeRoot

.gitignore

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+node_modules

merkleTreeRoot.circom

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+
+
+
+pragma circom 2.0.0;
+
+include "node_modules/circomlib/circuitsposeidon.circom";
+
+template CheckRoot(n) { // compute the root of a MerkleTree of n levels
+    //  Example with n = 4;
+    //
+    //      H(H(H(l_1),H(l_2)),H(H(l_4),H(l_5))) ---> Merkle root
+    //           /                      \
+    //          /                        \
+    //  H(H(l_1),H(l_2))          H(H(l_4),H(l_5))
+    //     /    \                     /      \
+    //    /      \                   /        \
+    //  H(l_1)  H(l_2)             H(l_4)    H(l_5)
+    //    |       |                  |         |
+    //   l_1     l_2                l_3       l_4
+    //
+    signal input leaves[2**n];
+    signal output root;
+
+    // components definition
+    component posHash1In[2**n];
+    component posHash2In[(2**n)-1];
+
+    // components initialitzation
+    for (var i = 0; i<(2**n); i++){
+        posHash1In[i] = Poseidon(1);
+        posHash1In[i].inputs[0] <== leaves[i]; // set leaves to one input hash inputs
+    }
+
+
+
+    for (var i = n-1; i >= 0 ; i--){
+        var z = 2**(n)-1;
+        for(var j = 2**(i+1)-2 ; j >= (2**i)-1 ; j--){
+            posHash2In[j] = Poseidon(2);
+            if(i == n-1){
+                posHash2In[j].inputs[1] <== posHash1In[z].out;
+                posHash2In[j].inputs[0] <== posHash1In[z-1].out;
+                z=z-2;
+            } else{
+                posHash2In[j].inputs[1] <== posHash2In[j*2+2].out;
+                posHash2In[j].inputs[0] <== posHash2In[j*2+1].out;
+            }
+
+        }
+    }
+
+
+    root <== posHash2In[0].out;
+
+}

package.json

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+{
+  "dependencies": {
+    "circomlib": "^2.0.5"
+  }
+}