import java.util.Scanner; public class Main { public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
    int n=sc.nextInt();
    int m=sc.nextInt();
    long k=sc.nextLong();
    int[]a=new int[n+2];
    int[]b=new int[m+2];
    long[]sumA=new long[n+2];
    long[]sumB=new long[m+2];
    for(int i=1;i<=n;i++) {//前缀和
    	a[i]=sc.nextInt();
    	sumA[i]=a[i]+sumA[i-1];
    }
    for(int i=1;i<=m;i++) {
    	b[i]=sc.nextInt();
    	sumB[i]=b[i]+sumB[i-1];
    }
          
    
    int max=0;
    for(int i=0;i<=n;i++) {//遍历sumA
    	if(sumA[i]>k)break;
    	
    	int l=0,r=m,j=0;
    	while(l<=r) {//二分找出当前最大sumB
    		int mid=l+(r-l)/2;
    		if(sumA[i]+sumB[l]<=k) {
    			l=mid+1;
    			j=mid;
    		}else {
    			r=mid-1;
    		}
    	}
    	max=Math.max(max, i+j);
    }
    System.out.println(max);
}   

}