unsigned c[2d5];
{
	ll@n,@m,@k,z=0;
	rep(m){
		ll@a--,@b--;
		c[a]|=1<<18;
		c[b]+=1;
	}
	rsortA(n,c);
	rep(i,n){
		if(!(c[i]&1<<18)&&i>k){
			break;
		}
		z+=max(0,k-(c[i]&(1<<18)-1));
	}
	wt(z);
}