n,m,q=io.read("*n","*n","*n")

sum={}
for i=0,n do
	sum[i]={}
	for j=0,n do
		sum[i][j]=0
	end
end

for i=1,m do
	l,r=io.read("*n","*n")
	sum[l][r]=sum[l][r]+1
end

for i=0,n do
	for j=1,n do
		sum[i][j]=sum[i][j-1]+sum[i][j]
	end
end

for i=0,n do
	for j=1,n do
		sum[j][i]=sum[j-1][i]+sum[j][i]
	end
end

for i=1,q do
	l,r=io.read("*n","*n")
	print(sum[r][r]-sum[l-1][r]-sum[r][l-1]+sum[l-1][l-1])
end