Create coinChangeMinimumNumberOfCoins.cpp

Author: avidLearnerInProgress

coinChangeMinimumNumberOfCoins.cpp

@@ -0,0 +1,31 @@
+class Solution {
+public:
+    int change(int amount, vector<int>& coins) {
+       
+        int denominations = coins.size();
+        int dp[denominations + 1][amount + 1];
+
+
+        //set first column as 1 as there is 1 way to get sum of 0 irrespective of any denomination of coin that we have 
+        for(int i=0; i<=denominations; i++) dp[i][0] = 1;
+
+        //set first row as 0 as irrespective of the sum, for 0 domination we will get 0 ways to reach upto sum
+        for(int j=1; j<=amount; j++) dp[0][j] = 0;
+
+
+        for(int i=1; i<=denominations; i++) {
+            for(int j=1; j<=amount; j++) {
+
+                //include exclude principle => similar to unbounded knapsack
+                if(coins[i-1] <= j) {
+                    //exclude + include
+                    dp[i][j] = dp[i-1][j] + dp[i][j - coins[i-1]];  //in include its i in row and not i-1 because of unbounded knapsack
+                }
+                else {
+                    dp[i][j] = dp[i-1][j];
+                }
+            }
+        }
+        return dp[denominations][amount]; //total number of ways, coins of x denomination can get upto target sum
+    }
+};