const input = require("fs").readFileSync("/dev/stdin", "utf8")

;(input => {

    const lines = input.split('\n')
    const [N, C, K] = lines[0].split(' ').map(Number)

    const T = []
    for (let i = 0; i < N; i++) {
      T[i] = lines[i + 1] - 0
    }
    T.sort((a, b) => a - b)

    let pas = 1
    let bus = 1
    let start = T[0]
    for (let i = 1; i < N; i++) {
        if (T[i] - start > K || pas >= C) {
            pas= 1
            bus++
            start = T[i]
        } else {
          pas++
        }
    }

    console.log(bus)

})(input)
