bzoj2014

分析：感动~~好不容易遇见道水题。。

#include<cstdio> #include<algorithm> #include<cstring> #include<cmath> #include<queue> #define fo(i,a,b) for(int i=a;i<=b;i++) #define fd(i,a,b) for(int i=a;i>=b;i--) using namespace std; int n; typedef long long ll; ll m; const int N=2e5+6; struct node { ll x,y; }a[N]; bool cmp(node a,node b) { return a.x<b.x; } int main() { scanf("%d%lld",&n,&m); fo(i,1,n)scanf("%lld%lld",&a[i].x,&a[i].y); sort(a+1,a+1+n,cmp); ll ans=0; fo(i,1,n) { ll k=m/a[i].x; if (k<a[i].y) { ans+=k; break; } m-=a[i].x*a[i].y; ans+=a[i].y; //if (k<a[i].y)break; } printf("%lld\n",ans); }