Marbles UVA - 10090

给定两种购买物品的方案：花费 c1元购买 n1 个物品，或者花费 c2c2​ 元购买 n2n2​ 个物品。

方案可以无限使用，询问购买 n个物品至少要多少元，若无法恰好购买到 n 个物品输出 failed

 

 

 

 

 

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#include <iostream> #include <algorithm> #include <cstring> #include <cmath> using namespace std; #define int long long int n; int gcd(int a,int b,int &x,int &y){     if (b == 0){         x=1; y=0; return a;     }     int t = gcd(b,a%b,y,x); y -= a/b*x;     return t; }     signed main(){     int c1,c2,n1,n2;     while(cin>>n&&n){         int x,y;         cin>>c1>>n1>>c2>>n2;         int g=gcd(n1,n2,x,y);         if(n%g){             cout<<"failed\n";continue;         }         x=x*n/g ,y= y*n/g ;                              int A=(int)ceil(-(double)x/(double)(n2/g)),         B=(int)floor((double)y/(double)(n1/g));         if(B<A){             cout<<"failed\n";continue;         }                   if(c1*(x+A*n2/g) +c2*(y-A*n1/g)<             c1*(x+B*n2/g) +c2*(y-B*n1/g)){                 cout<<(x+A*n2/g) << ' '<< (y-A*n1/g) <<endl;             }         else{             cout<<x+B*n2/g<<' '<<(y-B*n1/g)<<endl;         }     }  }