Sum of all the values in a list of dictionaries-CodePudding

I have this list of dictionaries and I need to get the sum of all the values inside it.

warehouses = { 
    "Warehouse Lisboa": [
        { "name": "apples", "tons": 4},
        { "name": "oranges", "tons": 10},
        { "name": "lemons", "tons": 50}
    ], 
    "Warehouse Cascais": { 
            "Branch 1": [
                { "name": "apples", "tons": 10},
                { "name": "oranges", "tons": 24}
            ],
            "Branch 2": [
                { "name": "apples", "tons": 16},
                { "name": "oranges", "tons": 8}
            ]
    }, 
    "Warehouse Oeiras": { 
            
            "Branch 1": { 
                "Sub Branch 1":{
                    "Sub sub Branch 1": [
                        { "name": "lemons", "tons": 10}       
                    ]
                } 
            },
            "Branch 2": [ 
                { "name": "apples", "tons": 3}    
            ]
    }
}

I tried this:

def stock_fruits(warehouses):
   
   
   
    return sum(warehouses.values())

but it gave error:

TypeError: unsupported operand type(s) for : 'int' and 'list'

CodePudding user response：

Consider using a depth-first search approach:

from typing import Union

def stock_fruits(curr: Union[dict, list]) -> int:
    if isinstance(curr, dict):
        return sum(stock_fruits(value) for value in curr.values())
    return sum(entry["tons"] for entry in curr)

warehouses = {
    "Warehouse Lisboa": [
        {"name": "apples", "tons": 4},
        {"name": "oranges", "tons": 10},
        {"name": "lemons", "tons": 50}
    ],
    "Warehouse Cascais": {
        "Branch 1": [
            {"name": "apples", "tons": 10},
            {"name": "oranges", "tons": 24}
        ],
        "Branch 2": [
            {"name": "apples", "tons": 16},
            {"name": "oranges", "tons": 8}
        ]
    },
    "Warehouse Oeiras": {
        "Branch 1": {
            "Sub Branch 1": {
                "Sub sub Branch 1": [
                    {"name": "lemons", "tons": 10}
                ]
            }
        },
        "Branch 2": [
            {"name": "apples", "tons": 3}
        ]
    }
}
print(f"{stock_fruits(warehouses) = }")

Output:

stock_fruits(warehouses) = 135

CodePudding user response：

You can use this function to compute the sum:

    def stock_fruits(warehouses):
        fruit_sum = 0

        queue = deque(list(warehouses.values()))
        while queue:
            node = queue.popleft()
            if isinstance(node, List):
                fruit_sum  = sum([item.get('tons', 0) for item in node])
            else:
                queue.extend(list(node.values()))

        return fruit_sum