#include <iostream>#include <queue>using namespace std;struct node{__int64 a,b;node(){}node(__int64 _a,__int64 _b){a=_a;b=_b;}};queue<node> Q;__int64 p[100005],h,a,b,c;int main(){while(scanf("%I64d",&h)!=-1){scanf("%I64d%I64d%I64d",&a,&b,&c);if(a>b) swap(a,b);node top,next;while(!Q.empty()) Q.pop();memset(p,-1,sizeof(p));p[0]=0;Q.push(node(0,0));while(!Q.empty()){top=Q.front();Q.pop();next=node((top.a+a)%c,top.b+a);if(p[next.a]==-1||p[next.a]>next.b){p[next.a]=next.b;Q.push(next);}next=node((top.a+b)%c,top.b+b);if(p[next.a]==-1||p[next.a]>next.b){p[next.a]=next.b;Q.push(next);}}__int64 ans=0,i;for(i=0;i<c&&i<h;i++) if(p[i]!=-1&&p[i]<h)ans+=(h-1-p[i])/c+1;printf("%I64dn",ans);}return 0;}
