class SegmentTree: __all__ = ['setval', 'pointupdate', 'segquery', 'segsearch_right', 'pointgetval'] def __init__(self, n=10**6, idetify_elt=-10**9, func=max): assert (func(idetify_elt, idetify_elt) == idetify_elt) self._n = n self._seg_length_half = 2**(n-1).bit_length() self._idetify_elt = idetify_elt self._seg = [idetify_elt]*(2*self._seg_length_half) self._func = func def setval(self, x_list): '''Set value : A = x_list''' assert (len(x_list) == self._n) # Set value at the bottom for i in range(self._n): self._seg[i+self._seg_length_half-1] = x_list[i] # Build value for i in range(self._seg_length_half-2, -1, -1): self._seg[i] = self._func(self._seg[2*i+1], self._seg[2*i+2]) def pointupdate(self, k, x): '''Update : A[k] = x ''' pos = k + self._seg_length_half - 1 # Set value at k-th self._seg[pos] = x # Build bottom-up while pos: pos = (pos-1)//2 self._seg[pos] = self._func(self._seg[pos*2+1], self._seg[pos*2+2]) def pointgetval(self, k): ''' Return A[k] ''' return self._seg[k + self._seg_length_half - 1] def segquery(self, left, right): ''' Return func(A[left], ... , A[right-1]) ''' # if not left < right if right <= left: return self._idetify_elt func_value = self._idetify_elt leftpos = left + self._seg_length_half - 1 # leftmost segment rightpos = right + self._seg_length_half - 2 # rightmost segment while leftpos < rightpos-1: if leftpos&1 == 0: # if leftpos is right-child func_value = self._func(func_value, self._seg[leftpos]) if rightpos&1 == 1: # if rightpos is leftchild func_value = self._func(func_value, self._seg[rightpos]) rightpos -= 1 # move up leftpos = leftpos//2 rightpos = (rightpos-1)//2 func_value = self._func(func_value, self._seg[leftpos]) if leftpos != rightpos: func_value = self._func(func_value, self._seg[rightpos]) return func_value def segsearch_right(self, condfunc, left=0): ''' Return min_i satisfying condfunc( func( A[left], ... , A[i])) if impossible : return n ''' # if impossible (ie. condfunc( func( A[left], ... , A[-1])) is False) if not condfunc(self._segquery(left, self._n)): return self._n # possible func_value = self._idetify_elt rightpos = left + self._seg_length_half - 1 while True: # while rightpos is the left-child, move bottom-up while rightpos&1 == 1: rightpos //= 2 # try up_value_trial = self._func(func_value, self._seg[rightpos]) if not condfunc(up_value_trial): # move up and right func_value = up_value_trial rightpos = (rightpos-1)//2 + 1 else: # move top-down while rightpos < self._seg_length_half-1: down_value_trial = self._func(func_value, self._seg[rightpos*2 + 1]) if condfunc(down_value_trial): # move left-child rightpos = rightpos*2 + 1 else: # move right-child func_value = down_value_trial rightpos = rightpos*2 + 2 return rightpos - self._seg_length_half + 1 n = int(input()) A = list(map(int, input().split())) D = [0 for _ in range(n - 23)] res = 0 for i in range(n): res += A[i] if i >= 23: D[i - 23] = res res -= A[i - 23] tree = SegmentTree(n - 23, 0, max) tree.setval(D) q = int(input()) for _ in range(q): t, v = map(int, input().split()) t -= 1 A[t] = v res = 0 num = 0 for i in range(max(0, t - 23), min(n, t + 24)): res += A[i] num += 1 if num >= 24: tree.pointupdate(i - 23, res) res -= A[i - 23] print(tree.segquery(0, n - 23))