#include <stdio.h>
#include <stdlib.h>

int main() {
    int n,x,returnNum=0;
    scanf("%d %d",&n,&x);
    for (int i = 0; i < n; i++) {
        int a,b;
        scanf("%d %d",&a,&b);
        if(abs(a-b)>=x)
            returnNum++;
    }

    printf("%d",returnNum);
}