Added CoinChange Algorithm (#260)

* Added CoinChange Algorithm

* Minor Changes

* Minor Changes

* Minor Changes

Dynamic-Programming/CoinChange.js

@@ -0,0 +1,45 @@
+function change (coins, amount) {
+  const combinations = new Array(amount + 1).fill(0)
+  combinations[0] = 1
+
+  for (let i = 0; i < coins.length; i++) {
+    const coin = coins[i]
+
+    for (let j = coin; j < amount + 1; j++) {
+      combinations[j] += combinations[j - coin]
+    }
+  }
+  return combinations[amount]
+}
+
+function minimumCoins (coins, amount) {
+  // minimumCoins[i] will store the minimum coins needed for amount i
+  const minimumCoins = new Array(amount + 1).fill(0)
+
+  minimumCoins[0] = 0
+
+  for (let i = 1; i < amount + 1; i++) {
+    minimumCoins[i] = Number.MAX_SAFE_INTEGER
+  }
+  for (let i = 1; i < amount + 1; i++) {
+    for (let j = 0; j < coins.length; j++) {
+      const coin = coins[j]
+      if (coin <= i) {
+        const subRes = minimumCoins[i - coin]
+        if (subRes !== Number.MAX_SAFE_INTEGER && subRes + 1 < minimumCoins[i]) {
+          minimumCoins[i] = subRes + 1
+        }
+      }
+    }
+  }
+  return minimumCoins[amount]
+}
+
+function main () {
+  const amount = 12
+  const coins = [2, 4, 5]
+  console.log('Number of combinations of getting change for ' + amount + ' is: ' + change(coins, amount))
+  console.log('Minimum number of coins required for amount :' + amount + ' is: ' + minimumCoins(coins, amount))
+}
+
+main()