11_Ones_and_Zeroes.cpp

// 474. Ones and Zeroes

// You are given an array of binary strings strs and two integers m and n.

// Return the size of the largest subset of strs such that there are at most m 0's and n 1's in the subset.

// A set x is a subset of a set y if all elements of x are also elements of y.

 

// Example 1:

// Input: strs = ["10","0001","111001","1","0"], m = 5, n = 3
// Output: 4
// Explanation: The largest subset with at most 5 0's and 3 1's is {"10", "0001", "1", "0"}, so the answer is 4.
// Other valid but smaller subsets include {"0001", "1"} and {"10", "1", "0"}.
// {"111001"} is an invalid subset because it contains 4 1's, greater than the maximum of 3.
// Example 2:

// Input: strs = ["10","0","1"], m = 1, n = 1
// Output: 2
// Explanation: The largest subset is {"0", "1"}, so the answer is 2.
 

// Constraints:

// 1 <= strs.length <= 600
// 1 <= strs[i].length <= 100
// strs[i] consists only of digits '0' and '1'.
// 1 <= m, n <= 100

class Solution
{
public:
    vector<int> counting(string s)
    {
        vector<int> count(2, 0);
        for (auto &c : s)
        {
            count[c - '0']++;
        }
        return count;
    }

    int findMaxForm(vector<string> &strs, int m, int n)
    {
        vector<vector<int>> dp(m + 1, vector<int>(n + 1));
        for (auto &s : strs)
        {
            vector<int> count = counting(s);
            for (int zero = m; zero >= count[0]; zero--)
            {
                for (int one = n; one >= count[1]; one--)
                {
                    dp[zero][one] = max(dp[zero - count[0]][one - count[1]] + 1, dp[zero][one]);
                }
            }
        }

        return dp[m][n];
    }
};