6 replaced http://codegolf.stackexchange.com/ with https://codegolf.stackexchange.com/
source | link

Javascript, 68 63 61 60 52 bytes

5 bytes off thanks @ETHproductions@ETHproductions. 2 3 11!! bytes off thanks @NotthatCharles@NotthatCharles.

f=(i,a,m=0)=>/[^01]/.test(i+=a[m++%10])?f(i,a,m):m/2

Test here.

Javascript, 68 63 61 60 52 bytes

5 bytes off thanks @ETHproductions. 2 3 11!! bytes off thanks @NotthatCharles.

f=(i,a,m=0)=>/[^01]/.test(i+=a[m++%10])?f(i,a,m):m/2

Test here.

Javascript, 68 63 61 60 52 bytes

5 bytes off thanks @ETHproductions. 2 3 11!! bytes off thanks @NotthatCharles.

f=(i,a,m=0)=>/[^01]/.test(i+=a[m++%10])?f(i,a,m):m/2

Test here.

5 @NotthatCharles is the guy !
source | link

Javascript, 68 63 61 6060 52 bytes

5 bytes off thanks @ETHproductions. 2 33 11!! bytes off thanks @NotthatCharles.

f=(i,a,r=.5,m=0)=>/[^01]/.test(i+=a[m++%10])?f(i,a,r+.5,m):rm/2

Test here.Test here.

Javascript, 68 63 61 60 bytes

5 bytes off thanks @ETHproductions. 2 3 bytes off thanks @NotthatCharles.

f=(i,a,r=.5,m=0)=>/[^01]/.test(i+=a[m++%10])?f(i,a,r+.5,m):r

Test here.

Javascript, 68 63 61 60 52 bytes

5 bytes off thanks @ETHproductions. 2 3 11!! bytes off thanks @NotthatCharles.

f=(i,a,m=0)=>/[^01]/.test(i+=a[m++%10])?f(i,a,m):m/2

Test here.

4 1 more byte thanks @NotthatCharles
source | link

Javascript, 68 63 6161 60 bytes

5 bytes off thanks @ETHproductions. 22 3 bytes off thanks @NotthatCharles.

f=(i,a,r=.5,m=-1m=0)=>/[^01]/.test(i+=a[++m%10]i+=a[m++%10])?f(i,a,r+.5,m):r

Test here.Test here.

Javascript, 68 63 61 bytes

5 bytes off thanks @ETHproductions. 2 bytes off thanks @NotthatCharles.

f=(i,a,r=.5,m=-1)=>/[^01]/.test(i+=a[++m%10])?f(i,a,r+.5,m):r

Test here.

Javascript, 68 63 61 60 bytes

5 bytes off thanks @ETHproductions. 2 3 bytes off thanks @NotthatCharles.

f=(i,a,r=.5,m=0)=>/[^01]/.test(i+=a[m++%10])?f(i,a,r+.5,m):r

Test here.

3 2 bytes off thanks @NotthatCharles.
source | link
2 5 bytes off thanks @ETHproductions.
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1
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