Create CoinChangeI.java

Author: harshithasudhakar

Dynamic Programming/2D/Subsequences/CoinChangeI.java

@@ -0,0 +1,36 @@
+class CoinChangeI { // Coin Change I 
+    public int coinChange(int[] coins, int amount) {
+        int n = coins.length;
+
+        int[][] dp = new int[n][amount+1];
+
+        // for(int i = 0; i<n; i++){
+        //     dp[i][0] = 0;
+        // }
+
+        for(int j = 0; j<amount+1; j++){
+            if(j % coins[0] == 0){
+                dp[0][j] = j/coins[0];
+            }
+            else{
+                dp[0][j] = (int)1e9;;
+            }
+        }
+
+        for(int i = 1; i<n; i++){
+            for(int j = 0; j<amount+1; j++){
+                int notPick = dp[i-1][j];
+                int pick = 0;
+                if(coins[i]<=j){
+                    pick = 1+dp[i][j-coins[i]];
+                }
+                else{
+                    pick = (int)1e9;
+                }
+                dp[i][j] = Math.min(notPick, pick);
+            }
+        }
+
+        return dp[n-1][amount] >= 1e9 ? -1 : dp[n-1][amount];
+    }
+}