def opMIN(x, y):
    return min(x, y)
def opMAX(x, y):
    return max(x, y)
def opSUM(x, y):
    return x+y
class UnionFind:
    def __init__(self, n, A, op):
        self.n = n
        self.parent_size = [-1]*n
        self.A = A[:]
        self.op = op
 
    def leader(self, a):
        if self.parent_size[a] < 0:
            return a
        self.parent_size[a] = self.leader(self.parent_size[a])
        return self.parent_size[a]
 
    def merge(self, a, b):
        x, y = self.leader(a), self.leader(b)
        if x == y:
            return 
        l, r = self.A[x], self.A[y]
        if abs(self.parent_size[x]) < abs(self.parent_size[y]):
            x, y = y, x
        self.parent_size[x] += self.parent_size[y]
        self.parent_size[y] = x
        self.A[x] = self.op(l, r)
        return 
    
    def __getitem__(self, n):
        return self.A[self.leader(n)]
    
    def update(self, n, a):
        self.A[self.leader(n)] = a
 
    def same(self, a, b):
        return self.leader(a) == self.leader(b)
 
    def size(self, a):
        return abs(self.parent_size[self.leader(a)])
 
    def groups(self):
        result = [[] for _ in range(self.n)]
        for i in range(self.n):
            result[self.leader(i)].append(i)
        return [r for r in result if r != []]

S = input()

if "1" not in S:
    exit(print(0))

UFL = UnionFind(len(S), list(range(len(S))), opMIN)
UFR = UnionFind(len(S), list(range(len(S))), opMAX)
UFD = UnionFind(len(S), [0]*len(S), opSUM)
for i in range(len(S)-1):
    if S[i] == "1" and S[i+1] == "1":
        UFL.merge(i, i+1)
        UFR.merge(i, i+1)
        UFD.merge(i, i+1)

A = []
for i in range(len(S)):
    if UFL.leader(i) == i and S[i] == "1":
        A.append(i)

ans = 0
for i in range(1, len(A)):
    if UFL.size(A[i-1])-UFD[A[i-1]] == 1:
        continue
    ans += (UFL[A[i]]-UFR[A[i-1]]-1)*((UFL.size(A[i-1])-UFD[A[i-1]])//2)
    if (UFD.size(A[i-1])-UFD[A[i-1]])%2 == 1:
        UFD.update(A[i-1], UFD[A[i-1]]+1)
    UFL.merge(A[i-1], A[i])
    UFR.merge(A[i-1], A[i])
    UFD.merge(A[i-1], A[i])
if 2 <= UFL.size(A[-1]):
    ans += (len(S)-1-UFR[A[-1]])*((UFL.size(A[-1])-UFD[A[-1]])//2)

print(ans)