#include <bits/stdc++.h>
using namespace std;
#define ll long long

int A,B,C,x;
int dirs[6][2]={{0,1},{0,2},{1,0},{1,2},{2,0},{2,1}};
bool vis[100][100][100];

struct node {
    int a,b,c;
    int steps;
    node(int aa,int bb,int cc,int ss):a(aa),b(bb),c(cc),steps(ss){}
};

int main(){
//	freopen("in.in","r",stdin);
	freopen("pourwater.in","r",stdin);
	freopen("pourwater.out","w",stdout);
    scanf("%lld %lld %lld %lld",&A,&B,&C,&x);
    if (x==0||x==A){
        printf("0");
        return 0;
    }else if (x<0||x>A){
    	printf("false");
        return 0;
    }else if (x>B&&x>C&&x!=A){
    	printf("false");
        return 0;
    }else if (A>B+C&&x<A-B-C){
    	printf("false");
        return 0;
    }
    queue<node> q;
    q.push(node(A,0,0,0));
    vis[A][0][0]=1;
    while (!q.empty()){
        node u=q.front();
        q.pop();
        for (int d=0; d<6; ++d){
            int from=dirs[d][0];
            int to=dirs[d][1];
            int a=u.a, b=u.b, c=u.c;
            if (from==0 && to==1){// A→B
                int amount=min(a,B-b);
                a-=amount;
                b+=amount;
            } else if (from==0 && to==2){// A→C
                int amount=min(a,C-c);
                a-=amount;
                c+=amount;
            } else if (from==1 && to==0){// B→A
                int amount=min(b,A-a);
                b-=amount;
                a+=amount;
            } else if (from==1 && to==2){// B→C
                int amount=min(b,C-c);
                b-=amount;
                c+=amount;
            } else if (from==2 && to==0){// C→A
                int amount=min(c,A-a);
                c-= amount;
                a+= amount;
            } else if (from==2 && to==1){// C→B
                int amount=min(c,B-b);
                c-=amount;
                b+=amount;
            }
            if (a<0||a>A||b<0||b>B||c<0||c>C)
                continue;
            if (vis[a][b][c])
                continue;
            if (a==x||b==x||c==x){
            	printf("%lld",u.steps+1);
                return 0;
            }
            vis[a][b][c]=1;
            q.push(node(a,b,c,u.steps+1));
        }
    }
    printf("false");
    return 0;
}