#define f(n)(x<1&y<1&n>z)*~(n-z)*(n-z)/2
long x,y,z,m,A,B;C,D,d;main(i){scanf("%ld%ld%d%d%d",&A,&B,&C,&D,&d);for(m=A*C<=0&B*D<=0;++i<6;z=(x*=A>0)+(y=B>1?B:1)-d,x-=C,y-=D,m-=f(1)-f(y)-f(x)+f(x+y-1))x=B,B=-C,C=D,D=-A,A=x;printf("%ld",m);}