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

#define REP(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) REP(i,0,n)

#define mygc(c) (c)=getchar_unlocked()
#define mypc(c) putchar_unlocked(c)

#define ll long long
#define ull unsigned ll

void reader(int *x){int k,m=0;*x=0;for(;;){mygc(k);if(k=='-'){m=1;break;}if('0'<=k&&k<='9'){*x=k-'0';break;}}for(;;){mygc(k);if(k<'0'||k>'9')break;*x=(*x)*10+k-'0';}if(m)(*x)=-(*x);}
void reader(ll *x){int k,m=0;*x=0;for(;;){mygc(k);if(k=='-'){m=1;break;}if('0'<=k&&k<='9'){*x=k-'0';break;}}for(;;){mygc(k);if(k<'0'||k>'9')break;*x=(*x)*10+k-'0';}if(m)(*x)=-(*x);}
void reader(double *x){scanf("%lf",x);}
int reader(char c[]){int i,s=0;for(;;){mygc(i);if(i!=' '&&i!='\n'&&i!='\r'&&i!='\t'&&i!=EOF) break;}c[s++]=i;for(;;){mygc(i);if(i==' '||i=='\n'||i=='\r'||i=='\t'||i==EOF) break;c[s++]=i;}c[s]='\0';return s;}
template <class T, class S> void reader(T *x, S *y){reader(x);reader(y);}
template <class T, class S, class U> void reader(T *x, S *y, U *z){reader(x);reader(y);reader(z);}
template <class T, class S, class U, class V> void reader(T *x, S *y, U *z, V *w){reader(x);reader(y);reader(z);reader(w);}

void writer(int x, char c){int s=0,m=0;char f[10];if(x<0)m=1,x=-x;while(x)f[s++]=x%10,x/=10;if(!s)f[s++]=0;if(m)mypc('-');while(s--)mypc(f[s]+'0');mypc(c);}
void writer(ll x, char c){int s=0,m=0;char f[20];if(x<0)m=1,x=-x;while(x)f[s++]=x%10,x/=10;if(!s)f[s++]=0;if(m)mypc('-');while(s--)mypc(f[s]+'0');mypc(c);}
void writer(double x, char c){printf("%.15f",x);mypc(c);}
void writer(const char c[]){int i;for(i=0;c[i]!='\0';i++)mypc(c[i]);}
void writer(const char x[], char c){int i;for(i=0;x[i]!='\0';i++)mypc(x[i]);mypc(c);}
template<class T> void writerLn(T x){writer(x,'\n');}
template<class T, class S> void writerLn(T x, S y){writer(x,' ');writer(y,'\n');}
template<class T, class S, class U> void writerLn(T x, S y, U z){writer(x,' ');writer(y,' ');writer(z,'\n');}
template<class T> void writerArr(T x[], int n){int i;if(!n){mypc('\n');return;}rep(i,n-1)writer(x[i],' ');writer(x[n-1],'\n');}

char memarr[17000000]; void *mem = memarr;
#define MD 1000000007

template<class T> T GCD(T a,T b){T r; while(a)r=b,b=a,a=r%a; return b;}
template<class T> T LCM(T a,T b){return a/GCD(a,b)*b;}
template<class T> T GCD(T a,T b,T c){return GCD(GCD(a,b),c);}
template<class T> T LCM(T a,T b,T c){return LCM(LCM(a,b),c);}
template<class T> void reduceFraction(T&a, T&b){T g=GCD(a,b);a/=g;b/=g;}

int getPrime(int N, int res[]){int i,a,b,s=1,f[4780],S=1;const int r=23000;bool B[r],*p=B;N/=2;res[0]=2;b=min(r,N);REP(i,1,b)p[i]=1;REP(i,1,b)if(p[i]){res[s++]=2*i+1;f[S]=2*i*(i+1);if(f[S]<N){for(;f[S]<r;f[S]+=res[S])p[f[S]]=0;S++;}}for(a=r;a<N;a+=r){b=min(a+r,N);p-=r;REP(i,a,b)p[i]=1;REP(i,1,S)for(;f[i]<b;f[i]+=res[i])p[f[i]]=0;REP(i,a,b)if(p[i])res[s++]=2*i+1;}return s;}
template<class T> int getFactors(ll n, T fac[], int num[], int ps, int p[]){int i,j,k,s=0;rep(i,ps){if((ll)p[i]*p[i]>n) break;if(n%p[i]==0){fac[s]=p[i];num[s]=0;while(n%p[i]==0)n/=p[i],num[s]++;s++;}}if(n>1)fac[s]=n,num[s++]=1;return s;}

template<class T> void sort(int N, T a[], void *mem = NULL){sort(a,a+N);}
template<class T1, class T2> void sort(int N, T1 a[], T2 b[], void *mem){int i;pair<T1,T2> *r=(pair<T1, T2>*)mem;rep(i,N)r[i].first=a[i],r[i].second=b[i];sort(r,r+N);rep(i,N)a[i]=r[i].first,b[i]=r[i].second;}
template<class T1, class T2, class T3> void sort(int N, T1 a[], T2 b[], T3 c[], void *mem){int i;pair<T1,pair<T2,T3> > *r=(pair<T1,pair<T2,T3> >*)mem;rep(i,N)r[i].first=a[i],r[i].second.first=b[i],r[i].second.second=c[i];sort(r,r+N);rep(i,N)a[i]=r[i].first,b[i]=r[i].second.first,c[i]=r[i].second.second;}
template<class T1, class T2, class T3, class T4> void sort(int N, T1 a[], T2 b[], T3 c[], T4 d[], void *mem){int i;pair<pair<T1,T2>,pair<T3,T4> > *r=(pair<pair<T1,T2>,pair<T3,T4> >*)mem;rep(i,N)r[i].first.first=a[i],r[i].first.second=b[i],r[i].second.first=c[i],r[i].second.second=d[i];sort(r,r+N);rep(i,N)a[i]=r[i].first.first,b[i]=r[i].first.second,c[i]=r[i].second.first,d[i]=r[i].second.second;}

template<class T> void unique(T arr[], int &sz, int sorted=0){int i,k=0;if(!sorted)sort(arr,arr+sz);rep(i,sz)if(!k||arr[k-1]!=arr[i])arr[k++]=arr[i];sz=k;}
template<class T, class S> void unique(T arr[], S val[], int &sz, void *mem, int sorted=0){int i,k=0;if(!sorted)sort(sz,arr,val,mem);rep(i,sz)if(!k||arr[k-1]!=arr[i])arr[k]=arr[i],val[k++]=val[i];else val[k-1] += val[i];sz=k;}
template<class T, class S, class V> void unique(T arr[], S v1[], V v2[], int &sz, void *mem, int sorted=0){int i,k=0;if(!sorted)sort(sz,arr,v1,v2,mem);rep(i,sz)if(!k||arr[k-1]!=arr[i])arr[k]=arr[i],v1[k]=v1[i],v2[k++]=v2[i];else v1[k-1] += v1[i],v2[k-1] += v2[i];sz = k;}


int ps, p[100000];
int fc[10000], num[10000];

int main(){
  int i, j, k;
  int T[3];
  ll up1, up2, dw1, dw2;
  ll up = 1, dw = 1;
  int mn, tmp;

  ps = getPrime(100000, p);

  rep(i,3) reader(T+i);
  sort(T, T+3);

  up1 = T[2] - T[0];
  dw1 = T[2] * T[0];
  up2 = T[2] - T[1];
  dw2 = T[2] * T[1];

  k = 0;
  k += getFactors(up1, fc+k, num, ps, p);
  k += getFactors(up2, fc+k, num, ps, p);
  k += getFactors(dw1, fc+k, num, ps, p);
  k += getFactors(dw2, fc+k, num, ps, p);

  unique(fc, k);

  rep(i,k){
    mn = 1000000;

    tmp = 0;
    while(up1 % fc[i]==0) up1 /= fc[i], tmp++;
    while(dw1 % fc[i]==0) dw1 /= fc[i], tmp--;
    mn = min(mn, tmp);


    tmp = 0;
    while(up2 % fc[i]==0) up2 /= fc[i], tmp++;
    while(dw2 % fc[i]==0) dw2 /= fc[i], tmp--;
    mn = min(mn, tmp);

    while(mn < 0){
      mn++;
      up *= fc[i];
    }
    while(mn > 0){
      mn--;
      dw *= fc[i];
    }
  }

  writer(up,'/');
  writerLn(dw);


  return 0;
}