+

lemonadeChange.dart

@@ -0,0 +1,30 @@
+// https://leetcode.com/problems/lemonade-change/
+
+void main(List<String> args) {
+  var bills = [5, 5, 10, 5, 20];
+  print(lemonadeChange(bills));
+}
+
+lemonadeChange(bills) {
+  int fives = 0;
+  int tens = 0;
+  for (int i = 0; i < bills.length; i++) {
+    if (bills[i] == 5) {
+      fives++;
+    } else if (bills[i] == 10) {
+      if (fives < 0) return false;
+      fives--;
+      tens++;
+    } else if (bills[i] == 20) {
+      if (tens == 0) {
+        if (fives < 3) return false;
+        fives -= 3;
+      } else {
+        if (fives < 1) return false;
+        tens--;
+        fives--;
+      }
+    }
+  }
+  return true;
+}

lemonadeChange.java

@@ -0,0 +1,28 @@
+// https://leetcode.com/problems/lemonade-change/
+
+
+class Solution {
+    public boolean lemonadeChange(int[] bills) {
+        int fives = 0;
+        int tens = 0;
+        for (int i = 0; i < bills.length; i++) {
+            if (bills[i] == 5) {
+            fives++;
+            } else if (bills[i] == 10) {
+            if (fives < 0) return false;
+            fives--;
+            tens++;
+            } else if (bills[i] == 20) {
+            if (tens == 0) {
+                if (fives < 3) return false;
+                fives -= 3;
+            } else {
+                if (fives < 1) return false;
+                tens--;
+                fives--;
+            }
+            }
+        }
+        return true;
+            }
+}

lemonadeChange.js

@@ -0,0 +1,27 @@
+// https://leetcode.com/problems/lemonade-change/
+
+var lemonadeChange = function (bills) {
+  let fives = 0;
+  let tens = 0;
+  for (let i = 0; i < bills.length; i++) {
+    if (bills[i] == 5) {
+      fives++;
+    } else if (bills[i] == 10) {
+      if (fives < 0) return false;
+      fives--;
+      tens++;
+    } else if (bills[i] == 20) {
+      if (tens == 0) {
+        if (fives < 3) return false;
+        fives -= 3;
+      } else {
+        if (fives < 1) return false;
+        tens--;
+        fives--;
+      }
+    }
+  }
+  return true;
+};
+
+console.log(lemonadeChange([5, 5, 10, 5, 20]));