PAT 1081. Rational Sum (20)

#include<stdio.h>
#include<iostream>
#include<math.h>

using namespace std;

long long a[101],b[101];

long long gcd(long long x,long long y)
{
return y?gcd(y,x%y):x;
}

int main(){

long long n,suma,sumb,sumc;

long long i,j,k;
scanf("%lld",&n);
for(i=0;i<n;i++)
scanf("%lld/%lld",&a[i],&b[i]);

long long temp1,temp2,temp;
temp1=a[0];temp2=b[0];
for(i=1;i<n;i++)
{
temp1=temp1*b[i]+temp2*a[i];
temp2=temp2*b[i];
//           temp=gcd(temp1,temp2);
//           temp1/=temp;
//           temp2/=temp;

}

//        printf("\n");
//        printf("%lld\n",temp);
//        printf("%lld %lld\n",temp1,temp2);
//        printf("\n");

if(temp1>=0)
{
temp=gcd(temp1,temp2);
temp1/=temp;
temp2/=temp;
suma=temp1/temp2;
sumb=temp1-suma*temp2;
sumc=temp2;
if(suma==0&&sumb!=0)
printf("%lld/%lld",sumb,sumc);

else if(sumb==0)
printf("%lld",suma);
else
printf("%lld %lld/%lld",suma,sumb,sumc);
}

else
{
temp1=-temp1;
temp=gcd(temp1,temp2);
temp1/=temp;
temp2/=temp;
suma=temp1/temp2;
sumb=temp1-suma*temp2;
sumc=temp2;

if(suma==0)
sumb=-sumb;
else
suma=-suma;

if(suma==0&&sumb!=0)
printf("%lld/%lld",sumb,sumc);

else if(sumb==0)
printf("%lld",suma);
else
printf("%lld %lld/%lld",suma,sumb,sumc);
}

return 0;
}

//2
//-1/3 2/3