# <editor-fold desc="Fast IO">
# !/usr/bin/env python
from __future__ import division, print_function

import os
import random
import sys
from io import BytesIO, IOBase

if sys.version_info[0] < 3:
    from __builtin__ import xrange as range
    from future_builtins import ascii, filter, hex, map, oct, zip

BUFFER_SIZE = 8192

DBG = os.environ.get('DBG')


class FastIO(IOBase):
    newlines = 0

    def __init__(self, file):
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = 'x' in file.mode or 'r' not in file.mode
        self.write = self.buffer.write if self.writable else None

    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFFER_SIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()

    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFFER_SIZE))
            self.newlines = b.count(b'\n') + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()

    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)


class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        self.write = lambda s: self.buffer.write(s.encode('ascii'))
        self.read = lambda: self.buffer.read().decode('ascii')
        self.readline = lambda: self.buffer.readline().decode('ascii')


def print(*args, **kwargs):
    """Prints the values to a stream, or to sys.stdout by default."""
    sep, file = kwargs.pop('sep', ' '), kwargs.pop('file', sys.stdout)
    at_start = True
    for x in args:
        if not at_start:
            file.write(sep)
        file.write(str(x))
        at_start = False
    file.write(kwargs.pop('end', '\n'))
    if kwargs.pop('flush', False):
        file.flush()


if sys.version_info[0] < 3:
    sys.stdin, sys.stdout = FastIO(sys.stdin), FastIO(sys.stdout)
else:
    sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)

input = lambda: sys.stdin.readline()


def cin_int_list():
    return [int(x) for x in sys.stdin.readline().split()]


def cin_int_iter():
    return (int(x) for x in sys.stdin.readline().split())


def cin_int():
    return int(input())


def cout_int_iter(a):
    print(' '.join(map(str, a)))


def iota(n, start=0):
    return list(range(start, n))


def cin_digits_list():
    return [ord(x) - ord('0') for x in input()]


# </editor-fold>


def solve(n, a):
    pos, neg = None, None
    sm = 0

    if a[0] > 0:
        pos = a[0]
    else:
        neg = a[0]

    for i in range(1, n):
        x = a[i]
        if x > 0:
            if pos is None:
                if neg is not None:
                    sm += neg
                    neg = None
                pos = x
            elif x > pos:
                pos = x
        else:
            if neg is None:
                if pos is not None:
                    sm += pos
                    pos = None
                neg = x
            elif x > neg:
                neg = x

    if pos is not None:
        sm += pos
    elif neg is not None:
        sm += neg

    return sm


def main():
    t = cin_int()

    for _ in range(t):
        n = cin_int()
        a = cin_int_list()
        print(solve(n, a))


if __name__ == '__main__':
    if DBG:
        import unittest


        class TestCase(unittest.TestCase):
            pass


        unittest.main()

        exit()

    main()
