translation: Add Python and Java code for EN version (#1345)

* Add the intial translation of code of all the languages

* test

* revert

* Remove

* Add Python and Java code for EN version

en/codes/python/chapter_greedy/coin_change_greedy.py

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+"""
+File: coin_change_greedy.py
+Created Time: 2023-07-18
+Author: krahets (krahets@163.com)
+"""
+
+
+def coin_change_greedy(coins: list[int], amt: int) -> int:
+    """Coin change: Greedy"""
+    # Assume coins list is ordered
+    i = len(coins) - 1
+    count = 0
+    # Loop for greedy selection until no remaining amount
+    while amt > 0:
+        # Find the smallest coin close to and less than the remaining amount
+        while i > 0 and coins[i] > amt:
+            i -= 1
+        # Choose coins[i]
+        amt -= coins[i]
+        count += 1
+    # If no feasible solution is found, return -1
+    return count if amt == 0 else -1
+
+
+"""Driver Code"""
+if __name__ == "__main__":
+    # Greedy: can ensure finding a global optimal solution
+    coins = [1, 5, 10, 20, 50, 100]
+    amt = 186
+    res = coin_change_greedy(coins, amt)
+    print(f"\ncoins = {coins}, amt = {amt}")
+    print(f"The minimum number of coins needed to make up {amt} is {res}")
+
+    # Greedy: cannot ensure finding a global optimal solution
+    coins = [1, 20, 50]
+    amt = 60
+    res = coin_change_greedy(coins, amt)
+    print(f"\ncoins = {coins}, amt = {amt}")
+    print(f"The minimum number of coins needed to make up {amt} is {res}")
+    print(f"In reality, the minimum number needed is 3, i.e., 20 + 20 + 20")
+
+    # Greedy: cannot ensure finding a global optimal solution
+    coins = [1, 49, 50]
+    amt = 98
+    res = coin_change_greedy(coins, amt)
+    print(f"\ncoins = {coins}, amt = {amt}")
+    print(f"The minimum number of coins needed to make up {amt} is {res}")
+    print(f"In reality, the minimum number needed is 2, i.e., 49 + 49")

en/codes/python/chapter_greedy/fractional_knapsack.py

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+"""
+File: fractional_knapsack.py
+Created Time: 2023-07-19
+Author: krahets (krahets@163.com)
+"""
+
+
+class Item:
+    """Item"""
+
+    def __init__(self, w: int, v: int):
+        self.w = w  # Item weight
+        self.v = v  # Item value
+
+
+def fractional_knapsack(wgt: list[int], val: list[int], cap: int) -> int:
+    """Fractional knapsack: Greedy"""
+    # Create an item list, containing two properties: weight, value
+    items = [Item(w, v) for w, v in zip(wgt, val)]
+    # Sort by unit value item.v / item.w from high to low
+    items.sort(key=lambda item: item.v / item.w, reverse=True)
+    # Loop for greedy selection
+    res = 0
+    for item in items:
+        if item.w <= cap:
+            # If the remaining capacity is sufficient, put the entire item into the knapsack
+            res += item.v
+            cap -= item.w
+        else:
+            # If the remaining capacity is insufficient, put part of the item into the knapsack
+            res += (item.v / item.w) * cap
+            # No remaining capacity left, thus break the loop
+            break
+    return res
+
+
+"""Driver Code"""
+if __name__ == "__main__":
+    wgt = [10, 20, 30, 40, 50]
+    val = [50, 120, 150, 210, 240]
+    cap = 50
+    n = len(wgt)
+
+    # Greedy algorithm
+    res = fractional_knapsack(wgt, val, cap)
+    print(f"The maximum item value without exceeding knapsack capacity is {res}")

en/codes/python/chapter_greedy/max_capacity.py

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+"""
+File: max_capacity.py
+Created Time: 2023-07-21
+Author: krahets (krahets@163.com)
+"""
+
+
+def max_capacity(ht: list[int]) -> int:
+    """Maximum capacity: Greedy"""
+    # Initialize i, j, making them split the array at both ends
+    i, j = 0, len(ht) - 1
+    # Initial maximum capacity is 0
+    res = 0
+    # Loop for greedy selection until the two boards meet
+    while i < j:
+        # Update maximum capacity
+        cap = min(ht[i], ht[j]) * (j - i)
+        res = max(res, cap)
+        # Move the shorter board inward
+        if ht[i] < ht[j]:
+            i += 1
+        else:
+            j -= 1
+    return res
+
+
+"""Driver Code"""
+if __name__ == "__main__":
+    ht = [3, 8, 5, 2, 7, 7, 3, 4]
+
+    # Greedy algorithm
+    res = max_capacity(ht)
+    print(f"Maximum capacity is {res}")

en/codes/python/chapter_greedy/max_product_cutting.py

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+"""
+File: max_product_cutting.py
+Created Time: 2023-07-21
+Author: krahets (krahets@163.com)
+"""
+
+import math
+
+
+def max_product_cutting(n: int) -> int:
+    """Maximum product of cutting: Greedy"""
+    # When n <= 3, must cut out a 1
+    if n <= 3:
+        return 1 * (n - 1)
+    # Greedy cut out 3s, a is the number of 3s, b is the remainder
+    a, b = n // 3, n % 3
+    if b == 1:
+        # When the remainder is 1, convert a pair of 1 * 3 into 2 * 2
+        return int(math.pow(3, a - 1)) * 2 * 2
+    if b == 2:
+        # When the remainder is 2, do nothing
+        return int(math.pow(3, a)) * 2
+    # When the remainder is 0, do nothing
+    return int(math.pow(3, a))
+
+
+"""Driver Code"""
+if __name__ == "__main__":
+    n = 58
+
+    # Greedy algorithm
+    res = max_product_cutting(n)
+    print(f"Maximum product of cutting is {res}")