usaco 2.1.2 frac1

/*ID: cm750621PROB: frac1LANG: C++*/#include <cstdio>#include <cstdlib>int i,j,k,m,n;void sch(int a1,int a2,int b1,int b2){     if(a1+b1>n || a2+b2>n)     return;     else{         int m1=a1+b1,m2=a2+b2;         sch(a1,a2,m1,m2);         printf("%d/%d\n",a1+b1,a2+b2);          sch(m1,m2,b1,b2);     }}int main(){    freopen("frac1.in","r",stdin);    freopen("frac1.out","w",stdout);    scanf("%d",&n);    printf("0/1\n");    sch(0,1,1,1);    printf("1/1\n");}