'use strict'
const lines = require('fs').readFileSync(0, 'utf8').split('\n')
const nmq = lines[0].split(' ')
const N = parseInt(nmq[0], 10)
const M = parseInt(nmq[1], 10)
const Q = parseInt(nmq[2], 10)
const dp = Array(N)
for (let l=0;l < N;l++) {
  dp[l] = Array(N-l)
}
for (let i=1;i <= M;i++) {
  const LR = lines[i].split(' ')
  const L = parseInt(LR[0], 10)
  const R = parseInt(LR[1], 10)
  for (let l=0;l < L;l++) {
    for (let r=R-l-1;r < N-l;r++) {
      const count = dp[l][r] || 0
      dp[l][r] = count + 1
    }
  }
}
for (let i=M+1;i <= M+Q;i++) {
  const pq = lines[i].split(' ')
  const p = parseInt(pq[0], 10)
  const q = parseInt(pq[1], 10)
  console.log(dp[p-1][q-p] || 0)
}