#include <stdio.h>
#include "malloc.h"
//#include <mm_malloc.h>
#include <stdlib.h>
int *needPaint;
int *leftPaint;
int colorType;
int graySize;
int cmp(const void *p,const void *q)
{
return *(int*)p<*(int*)q?1:-1;
}
int kitN(){
int k;
int j;
int currentKit = 0;
qsort(needPaint,colorType ,sizeof(int),cmp);
if(needPaint[0]%50==0)
currentKit =needPaint[0]/50;
else
currentKit = needPaint[0]/50+1;
for(j=0;j<colorType;j++){
leftPaint[j] = currentKit*50-needPaint[j];
}
while(graySize>0){
qsort(leftPaint,colorType ,sizeof(int),cmp);
if(leftPaint[2]==0){
currentKit++;
for(k=0;k<colorType;k++){
leftPaint[k] += 50;
}
graySize--;
}else{
graySize--;
leftPaint[0]--;
leftPaint[1]--;
leftPaint[2]--;
qsort(leftPaint,colorType ,sizeof(int),cmp);
}
}
return currentKit;
}
int main() {
while(scanf("%d",&colorType) && colorType){
int i;
needPaint = (int*)malloc(sizeof(int)*(colorType));
leftPaint =(int*)malloc(sizeof(int)*(colorType));
for(i=0;i<colorType;i++){
scanf("%d",&needPaint[i]);
}
scanf("%d",&graySize);
printf("%d\n",kitN());
}
return 0;
}
