#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> P;
const ll INF=1e18;
struct SegTree{
vector<ll> tree, lazy;
int base;
SegTree(int a){
base=1;
while(base<a) base<<=1;
tree.resize(base*2+2);
lazy.resize(base*2+2);
base--;
}
void setup(int a){
base=1;
while(base<a) base<<=1;
for(int i=1 ; i<base*2 ; i++) tree[i]=lazy[i]=0;
for(int i=base+a ; i<base*2 ; i++) tree[i]=INF;
for(int i=base-1 ; i>=1 ; i--) tree[i]=min(tree[i*2],tree[i*2+1]);
base--;
}
void propagate(int ns, int nf, int num){
if(lazy[num]!=0){
if(ns<nf){
lazy[num*2]+=lazy[num];
lazy[num*2+1]+=lazy[num];
}
tree[num]+=lazy[num];
lazy[num]=0;
}
}
ll query(int ns=1, int nf=-1, int num=1){
if(nf==-1) nf=base+1;
propagate(ns,nf,num);
return tree[num];
}
void add_value(ll val, int st, int fn, int ns=1, int nf=-1, int num=1){
if(nf==-1) nf=base+1;
propagate(ns,nf,num);
if(ns>fn || nf<st) return;
if(st<=ns && nf<=fn){
lazy[num]+=val;
propagate(ns,nf,num);
return;
}
int mid=(ns+nf)>>1;
add_value(val,st,fn,ns,mid,num*2);
add_value(val,st,fn,mid+1,nf,num*2+1);
tree[num]=min(tree[num*2],tree[num*2+1]);
}
};
struct A{
int x1, y1, x2, y2, c;
A(){}
A(int t1, int t2, int t3, int t4, int t5) : x1(t1), y1(t2), x2(t3), y2(t4), c(t5) {}
};
bool cmp(const A &lhs, const A &rhs){
return lhs.y1<rhs.y1;
}
bool cmp2(const A &lhs, const A &rhs){
return lhs.y2<rhs.y2;
}
int m, n, p;
ll b;
A ob[400005], ob2[400005];
SegTree T(1000005);
bool pos(int w)
{
T.setup(m-w+1);
int idx=1, idx2=1, st, fn, k;
for(int sy=1, fy=w ; fy<=n ; sy++, fy++){
while(idx<=p && ob[idx].y1>=sy && ob[idx].y1<=fy){
st=max(1,ob[idx].x1-w+1);
fn=min(m-w+1,ob[idx].x2);
T.add_value(ob[idx].c,st,fn);
idx++;
}
while(idx2<=p && ob2[idx2].y2<sy){
st=max(1,ob2[idx2].x1-w+1);
fn=min(m-w+1,ob2[idx2].x2);
T.add_value(-ob2[idx2].c,st,fn);
idx2++;
}
if(T.query()<=b) return true;
}
return false;
}
int main()
{
scanf("%d %d",&m,&n);
scanf("%lld",&b);
scanf("%d",&p);
for(int i=1 ; i<=p ; i++){
scanf("%d %d %d %d %d",&ob[i].x1,&ob[i].y1,&ob[i].x2,&ob[i].y2,&ob[i].c);
ob2[i]=ob[i];
}
sort(ob+1,ob+1+p,cmp);
sort(ob2+1,ob2+1+p,cmp2);
int st=1, fn=min(m,n), mid, ans=0;
while(st<=fn){
mid=(st+fn)>>1;
if(pos(mid)) st=mid+1, ans=mid;
else fn=mid-1;
}
printf("%d",ans);
return 0;
}
