class FenwickTree:
    def __init__(self, n: int):
        self.data = [0] * (n+10)
        self.n = (n+10)

    def add(self, p: int, x: int):
        assert 0 <= p < self.n
        p += 1
        while p < len(self.data):
            self.data[p] += x
            p += p & -p

    def sum(self, p: int) -> int:
        """区間 [0, p] の和"""
        assert 0 <= p < self.n
        p += 1
        s = 0
        while p > 0:
            s += self.data[p]
            p -= p & -p
        return s

    def rangesum(self, l: int, r: int) -> int:
        """区間 [l, r] の和"""
        assert 0 <= l <= r < self.n
        s = self.sum(r)
        if l > 0:
            s -= self.sum(l-1)
        return s


L_DATA = 0
QUERY  = 1
R_DATA = 2

N, K, Q = map(int, input().split())

events = []
colors = []
for i in range(K):
    L, R, C, H = map(int, input().split())
    L -= 1
    R -= 1
    events.append((L, L_DATA, C, H, i))
    events.append((R, R_DATA, C, H, i))
    colors.append(C)

for i in range(Q):
    I, X = map(int, input().split())
    I -= 1
    events.append((I, QUERY, X, i))

events.sort()

size = 2*10**5 + 10
ft = FenwickTree(size)
ans = [0] * Q
for i in range(len(events)):
    e = events[i]
    if e[1] == L_DATA:
        c, h, di = e[2], e[3], e[4]
        ft.add(di, h)
    elif e[1] == R_DATA:
        c, h, di = e[2], e[3], e[4]
        ft.add(di, -h)
    elif e[1] == QUERY:
        ind, x, qi = e[0], e[2], e[3]
        if ft.sum(size) < x:
            ans[qi] = -1
        else:
            lo = 0
            hi = size
            res = hi
            while lo <= hi:
                m = (lo + hi) // 2
                if ft.sum(m) >= x:
                    res = min(res, m)
                    hi = m - 1
                else:
                    lo = m + 1

            ans[qi] = colors[res]
    else:
        assert False

print(*ans, sep='\n')