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#include <iostream>
#include <vector>
#include <cstring>
#include <unordered_map>
#include <queue>

const int M = 1'000'000'007;

class Solution {
public:
    int countSubMultisets(std::vector<int>& nums, int l, int r) {
        std::vector<int> dp(r + 1, 0);
        std::unordered_map<int, int> occ;
        
        for (int num : nums) {
            ++occ[num];
        }
        
        dp[0] = 1;
        for (auto& pair : occ) {
            if (!pair.first) {
                continue;
            }
            int offset = (1 + pair.second) * pair.first;
            std::queue<int> q;
            for (int i = 0; i <= r; ++i) {
                if (i + offset <= r) {
                    q.push(dp[i]);
                }
                if (i >= pair.first) {
                    dp[i] = (dp[i] + dp[i - pair.first]) % M;
                }
                if (i >= offset) {
                    dp[i] = (dp[i] + M - q.front()) % M;
                    q.pop();
                }
            }
        }
        
        long long res = 0;
        for (int i = l; i <= r; ++i) {
            res += dp[i];
        }
        
        return (res * (occ[0] + 1)) % M;
    }
};