Part A and B done

src/04a.js

@@ -176,6 +176,20 @@ function checkAdjacent(rowIdx, colIdx) {
     }
 }
 
+/**
+ * @param {Array} moveablePositions [rowIdx, colIdx] of all positions in which the roll can be removed
+ * @returns {Number} How many rolls were removed
+ */
+function removeRolls(moveablePositions) {
+    let removed = 0;
+    moveablePositions.forEach(pos => {
+        const row = rows[pos[0]];
+        row[pos[1]] = '.';
+        removed++;
+    });
+    return removed;
+}
+
 const rows = new Array();
 inputs.forEach(row => {
     const cols = parseRow(row);
@@ -183,14 +197,24 @@ inputs.forEach(row => {
     return;
 });
 
-let moveableCount = 0;
-for (let rowIdx = 0; rowIdx < rows.length; rowIdx++) {
-    for (let colIdx = 0; colIdx < rows[rowIdx].length; colIdx++) {
-        const row = rows[rowIdx];
-        const value = row[colIdx];
-        if (value === '@') {
-            if (checkAdjacent(rowIdx, colIdx)) moveableCount++;
+let done = false;
+let totalRemoved = 0;
+while (!done) {
+    let moveableCount = 0;
+    const moveablePositions = new Array();
+    for (let rowIdx = 0; rowIdx < rows.length; rowIdx++) {
+        for (let colIdx = 0; colIdx < rows[rowIdx].length; colIdx++) {
+            const row = rows[rowIdx];
+            const value = row[colIdx];
+            if (value === '@') {
+                if (checkAdjacent(rowIdx, colIdx)) {
+                    moveableCount++;
+                    moveablePositions.push([rowIdx, colIdx]);
+                }
+            }
         }
     }
+    totalRemoved += removeRolls(moveablePositions);
+    if (moveableCount === 0) done = true;
 }
-console.log(moveableCount);
+console.log(totalRemoved);