#include <cstdio> #include <cmath> #define M 100010 int a[M], n, k, m, max; int ok(int ans) { long long cnt = 0; for(int i = 0; i < n; i++) if(a[i]>ans) { int t = ceil(1.0*(a[i]-ans)/(k-1)); if(t>ans) return 0; cnt+=t; } return cnt<=(long long)ans*m; } int solve() { int l = 0, r = max, mid; if(k==1) return max; while(l<r) { mid = (r+l)>>1; if(ok(mid)) r = mid; else l = mid+1; } return l; } int main () { int cas; scanf("%d",&cas); while(cas--) { max = 0; scanf("%d",&n); for(int i = 0; i < n; i++) {scanf("%d",&a[i]); max = a[i]>max?a[i]:max; } scanf("%d%d",&m,&k); printf("%dn",solve()); } return 0; }
