#include<bits/stdc++.h>
#define int long long
using namespace std;
signed main(){
	int a,b;
	cin>>a>>b;
	cout<<(double)(a-b)/a*100.0;
	return 0;
}
#include<bits/stdc++.h>
#define pb push_back
#define Int long long
using namespace std;

long long N,M,K;
long long h,w;
long long X,Y,Z;
long long B;


const int MOD=1e9+7;

const int MAXN=5e5+5;
const int NAX=1005;
vector<int> adj[MAXN];
vector<Int> A;

Int ceilS(Int x,Int y){
    return (x+y-1)/y;
}

Int perform(Int x){
    return (x*(x+1))/2LL;
}


long long ModExpo(long long x,unsigned long long y,long long M){
    Int ans=1;
    ans=(long long)ans;
    
    while(y>0){
        if(y&1) ans=((ans%M)*(x%M))%M;
        y>>=1LL;
        x=((x%M)*(x%M))%M;
    }
    return ans%M;
}

long long ModInv(long long x){
    return ModExpo(x,MOD-2,MOD);
}
Int madd(Int x,Int y){
    return (x+y)%MOD;
}

Int mmul(Int x,Int y){
    return ((x%MOD)*(y%MOD))%MOD;
}
vector<long long> fac(MAXN);

Int performMod(Int x){
    return mmul(mmul(x,x+1),ModInv(2))%MOD;
}

void fill(){
    fac[0]=1;
    for(int i=1;i<MAXN;++i){
        fac[i]=mmul(fac[i-1],i)%MOD;
    }
}
long long choose(long long n,long long r){
    if(r==0||r==n) return 1;
    if(r>n) return 0;

    return mmul(mmul(fac[n],ModInv(fac[n-r])),ModInv(fac[r]))%MOD;
}


const int INF=1e9;
using D=long double;

vector<pair<int64_t,int64_t>> factorize(int64_t x){

    vector<pair<int64_t,int64_t>> factors;

    for(int64_t i=2;i*i<=x;++i){
        if(x % i) continue;
        int cnt=0;

        while(x % i ==0){
            x/=i;
            ++cnt;
        }
        factors.pb({i,cnt});
    }
    if(x > 1){
        factors.pb({x,1});
    }
    return factors;
}
struct Fenwick{
    vector<long long> BIT;
    int n;

        Fenwick(int n){
            BIT.resize(n);
            BIT.assign(n,0);
            this->n=n;
        }
        void add(int x,int value){
            while(x<n){
                BIT[x]+=value;
                x+=(x&(-x));
            }
        }
        long long sum(int x){
            long long answer=0;
            while(x){
                answer+=BIT[x];
                x-=(x&(-x));
            }
            return answer;
        }
        
        long long rangeSum(int L,int R){
            return sum(R)-sum(L-1);
        }
};


int main()
{
    #ifndef ONLINE_JUDGE
    freopen("inputf.txt","r",stdin);
    freopen("outputf.txt","w",stdout);
    #endif

    ios_base::sync_with_stdio(false);cin.tie(0);
    cout.tie(0);

    
    D a,b;
    cin>>a>>b;
    cout<<fixed<<setprecision(18)<<( a - b) / a * 100<<'\n';
    

}