d,g=list(map(int,input().split()))

data=[]

cp=[]

for  i in range(1,d+1):

    p,c=list(map(int,input().split()))

    data.append(p)

    cp.append(c)

a=99999999

for i in range(1024):

    ct=0

    ans=0

    tmp=data[:]

    for j in range(d):

        if i&(1<<j):

            ct+=100*(j+1)*data[j]+cp[j]

            ans+=data[j]

            tmp[j]=0

            

    p=len(tmp)-1

    while ct<g :

        if tmp[p]>1:

            ct+=100*(p+1)

            tmp[p]-=1

            ans+=1

        else:

            p-=1

        if p<0:

            ans=99999999

            break

    a=min(a,ans)

print(a)

    
d,g=list(map(int,input().split()))

data=[]

for i in range(d):

    p,c=list(map(int,input().split()))

    data.append((p,c))

n=0

mn=99999999

while n<2**d:

    point=0

    count=0

    for i in range(d):

        if n&(1<<i):

            point+=data[i][0]*100*(i+1)+data[i][1]

            count+=data[i][0]

    if point<g:

        for i in range(d):

            i=d-1-i

            if not n&(1<<i):

                for j in range(data[i][0]-1):

                    point+=(i+1)*100

                    count+=1

                    if point>=g:

                        mn=min(mn,count)

                        break

                else:

                    break

                break

    else:

        mn=min(mn,count)

    n+=1

print(mn)



d, g = list(map(int, input().split()))
data = []
cp = []
for i in range(1, d + 1):
    p, c = list(map(int, input().split()))
    data.append(p)
    cp.append(c)
a = 99999999
for i in range(1024):
    ct = 0
    ans = 0
    tmp = data[:]
    for j in range(d):
        if i & (1 << j):
            ct += 100 * (j + 1) * data[j] + cp[j]
            ans += data[j]
            tmp[j] = 0
    p = len(tmp) - 1
    while ct < g:
        if tmp[p] > 1:
            ct += 100 * (p + 1)
            tmp[p] -= 1
            ans += 1
        else:
            p -= 1
        if p < 0:
            ans = 99999999
            break
    a = min(a, ans)
print(a)

d, g = list(map(int, input().split()))
data = []
for i in range(d):
    p, c = list(map(int, input().split()))
    data.append((p, c))
n = 0
mn = 99999999
while n < 2**d:
    point = 0
    count = 0
    for i in range(d):
        if n & (1 << i):
            point += data[i][0] * 100 * (i + 1) + data[i][1]
            count += data[i][0]
    if point < g:
        for i in range(d):
            i = d - 1 - i
            if not n & (1 << i):
                for j in range(data[i][0] - 1):
                    point += (i + 1) * 100
                    count += 1
                    if point >= g:
                        mn = min(mn, count)
                        break
                else:
                    break
                break
    else:
        mn = min(mn, count)
    n += 1
print(mn)

-cp = [] -for i in range(1, d + 1): +for i in range(d): -    data.append(p) -    cp.append(c) -a = 99999999 -for i in range(1024): -    ct = 0 -    ans = 0 -    tmp = data[:] -    for j in range(d): -        if i & (1 << j): -            ct += 100 * (j + 1) * data[j] + cp[j] -            ans += data[j] -            tmp[j] = 0 -    p = len(tmp) - 1 -    while ct < g: -        if tmp[p] > 1: -            ct += 100 * (p + 1) -            tmp[p] -= 1 -            ans += 1 -        else: -            p -= 1 -        if p < 0: -            ans = 99999999 -            break -    a = min(a, ans) -print(a) +    data.append((p, c)) +n = 0 +mn = 99999999 +while n < 2**d: +    point = 0 +    count = 0 +    for i in range(d): +        if n & (1 << i): +            point += data[i][0] * 100 * (i + 1) + data[i][1] +            count += data[i][0] +    if point < g: +        for i in range(d): +            i = d - 1 - i +            if not n & (1 << i): +                for j in range(data[i][0] - 1): +                    point += (i + 1) * 100 +                    count += 1 +                    if point >= g: +                        mn = min(mn, count) +                        break +                else: +                    break +                break +    else: +        mn = min(mn, count) +    n += 1 +print(mn)