C :

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

struct num{
	int b,c;
}a[10002];

int cmp(const void *x,const void *y){
	struct num * a1=(struct num *)x;
	struct num * a2=(struct num *)y;
	if(a1->c!=a2->c)
		return (a1->c<a2->c)?-1:1;
	else
		return (a1->b<a2->b)?-1:1;
}

int main()
{
	int m;
	scanf("%d",&m);
	while(m--){
		int n,i,p,count=1;
		scanf("%d",&n);
		for(i=0;i<n;i++)
			scanf("%d%d",&a[i].b,&a[i].c);

		qsort(a,n,sizeof(a[0]),cmp);

		p=a[0].c;
		
		for(i=1;i<n;i++){
			if(a[i].b>p){
				count++;
				p=a[i].c;
			}
		}
		printf("%d\n",count);
	}
	return 0;
}

C++ :

 #include<stdio.h>
 #include<string.h>
 #include<iostream>
 #include<algorithm>
 using namespace std;
 struct node
 {
    int start;
    int end;
 }s[10003];
 bool cmp(node x,node y)
 {
    if(x.end==y.end)
    return x.start>y.start;
    return x.end<y.end;
 }
 int main()
 {
     int test,num,n,flag,i;
     scanf("%d",&test);
     while(test--)
     {
         num = 1;
         scanf("%d",&n);
         for(i=0;i<n;i++)
         scanf("%d%d",&s[i].start,&s[i].end);
         sort(s,s+n,cmp);
         flag = s[0].end;
         for(i=1;i<n;i++)
         if(s[i].start>flag)
         {
            num ++;
            flag = s[i].end;
         }
         printf("%d\n",num);

    }
    return 0;
 }