function maximumSum(a, m) {
    let cur =0; let max =0;
    let x = [];
    a.forEach(e=>{
        let b=e%m;
        x.push(b);
        cur +=b;
        while(cur>=m){
            cur -=x.shift();
        }
        max =Math.max(max,cur)
        
    })
    return max
}

public static long maximumSum(List<long> a, long m)
    {
        long res = 0;
        
        for(int i = 0; i < a.Count; i++)
        {
            long sum = 0;
            
            for(int j = i; j < a.Count; j++)
            {
                sum = (a[j] + sum) % m;
                
                if(sum > res)
                    res = sum;
                if(res == m-1)
                    return res;
            }
        }
        return res;
    }

    public static long maximumSum(List<Long> a, long m) {
        // Write your code here
        TreeSet<Long> set = new TreeSet<>();
        long mod = 0, max = 0;
        for (long num : a) {
            mod = (mod + num % m) % m;
            max = mod > max ? mod : max;
            Long next = set.ceiling(mod + 1);
            if (next != null) {
                max = Math.max(max, m - (next - mod));
            }
            set.add(mod);
        }
        return max;
    }

def maximumSum(a, m):
    a = list(map(lambda x:x%m,itertools.accumulate(a)))
    maxi = max(a)
    arr = []
    for i in a:
        bisect.insort(arr,i)
        if i!=arr[-1]:
            maxi = max(maxi,(i-arr[bisect.bisect_right(arr,i)])%m)
    return maxi

long maximumSum(vector<long> a, long m) {
    sort(a.begin(),a.end());
    int s=0, end=m-1;
    long dp[a.size()]={0},i,j;
    for(i=0;i<a.size();i++){
        a[i]=a[i]%m;
    }
    dp[0]=a[0];
    long large=dp[0];
    for(i=1;i<a.size();i++){
        dp[i]=max(a[i],(a[i]+dp[i-1])%m);
        large=max(large,dp[i]);
    }
    return large;
    
    

}