```cpp // https://dashoj.com/p/77 #include <bits/stdc++.h> using namespace std; typedef long long ll; struct g { ll m; // 重量 ll u; // 价值 double x; // 每一重的价值 }; ll n, t; vector<g> gs; int main() { cin >> n >> t; for (int i = 0; i < n; i++) { ll m, u; cin >> m >> u; gs.push_back({m, u}); gs[i].x = (double) u / (double) m; } sort(gs.begin(), gs.end(), [](g a, g b) { return a.x > b.x; // 按价值 / 重量从大到小排序 }); double ans = 0; // 答案 for (int i = 0; i < n; ++i) { if (t >= gs[i].m) { t -= gs[i].m; ans += gs[i].u; } else { ans += t * gs[i].x; break; } } printf("%.2lf", ans); return 0; } ```

``` #include <iostream> #include <vector> #include <algorithm> using namespace std; struct Coin { int weight; int value; double density;//价值密度 }; bool compareDensity(const Coin& a, const Coin& b) { return a.density > b.density; } int main() { int N, T; cin >> N >> T; vector<Coin> coins(N); for (int i = 0; i < N; i++) { cin >> coins[i].weight >> coins[i].value; coins[i].density = (double)coins[i].value / coins[i].weight; } sort(coins.begin(), coins.end(), compareDensity); double totalValue = 0.0; int remainingWeight = T; for (int i = 0; i < N && remainingWeight > 0; i++) { if (coins[i].weight <= remainingWeight) { totalValue += coins[i].value; remainingWeight -= coins[i].weight; } else { totalValue += coins[i].density * remainingWeight; remainingWeight = 0; } } printf ("%.2f", totalValue); } ```

``` #include<iostream> #include<cstdio> #include<vector> #include<algorithm> using namespace std; struct node { int m,v; double x; }; bool cmp(node &a,node &b) { if(a.x>b.x) return 1; return 0; } vector<node> vec; int main() { int N,T,m,v; double x; cin>>N>>T; for(int i=0;i<N;i++) { cin>>m>>v; x=(double)v/(double)m; vec.push_back({m,v,x}); } double sum=0.0; sort(vec.begin(),vec.end(),cmp); for(int i=0;i<N;i++) { if(T==0) break; if(T>=vec[i].m) { sum+=vec[i].v; T-=vec[i].m; } else{ sum+=T*vec[i].x; T=0; } } printf("%.2lf",sum); } ```

70%,不知道哪里错了，有佬能帮看看嘛 ``` #include <bits/stdc++.h> using namespace std; struct Gold { int m; int v; double aver; bool operator<(const Gold& other) const { return aver < other.aver; } }; int main() { int N, T; int m, v; cin >> N >> T; double sum = 0; priority_queue<Gold> q; for(int i = 0; i < N; i++) { cin >> m >> v; q.push({m, v, (double)v/m}); } while(T > 0) { Gold g = q.top(); q.pop(); // 背包能装下现在的所有金币 if(T > g.m) { sum += g.v; } else { sum += T * g.aver; } T -= g.m; } printf("%.2lf", sum); } ```

``` #include <bits/stdc++.h> using namespace std; struct treasure{ //连锁数据排序 double m, v, rate; }; bool cmp(treasure a, treasure b) { return a.rate>b.rate; } int main() { int N, T; cin >> N >> T; vector<treasure> treasures(N); double sum=0; for(int i=0; i<N; i++) { cin >> treasures[i].m >> treasures[i].v; treasures[i].rate=treasures[i].v/treasures[i].m; } sort(treasures.begin(), treasures.end(), cmp); for(int i=0; i<N; i++) { if(T>=treasures[i].m) //尽量不造成出现负数的情况 { T-=treasures[i].m; sum+=treasures[i].v; } else { sum+=treasures[i].rate*T; T=0; break; } } printf("%.2lf", sum); return 0; } ```

include include include include using namespace std; struct gold { double value; double weight; double rate; }; bool cmp(const gold& t1,const gold& t2) { return t1.rate > t2.rate; } int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); int n, t; double numt = 0; double numv=0; vector v; cin >> n >> t; if (n 100 || t>1000)return 0; v.resize(n); for (int i = 0; i > v[i].weight >> v[i].value; if (v[i].value 120)return 0; v[i].rate = v[i].value / v[i].weight; } sort(v.begin(),v.end(),cmp); int i = 0; while (numt t) { numv-=(numt - t) v[i-1].rate; } cout << fixed<<setprecision(2)<<numv; return 0; }

``` #include<iostream> #include<string> #include<cmath> #include<algorithm> #include<cstdio> using namespace std; const int N=102; int n,zhilian; struct gold{ double weight; double worth; double every; }go[N]; bool compair(gold a,gold b){ return a.every>b.every; } int main(){ cin>>n>>zhilian; int i=0; int t=n; while(t--){ int x1,x2; scanf("%d%d",&x1,&x2); go[i].weight=x1,go[i].worth=x2; go[i].every=(double)x2/x1; i++; } sort(go,go+n,compair); double res=0; for(int j=0;j<n;j++){ if(zhilian>go[j].weight) res+=go[j].worth,zhilian-=go[j].weight; else { res+=go[j].every*zhilian; break; } } printf("%.2lf",res); return 0; } ```

/上天啊 难道你看不出我很爱她/ include using namespace std; struct Node{ double m,v; double avg; }a[110]; bool cmp(Node x,Node y) { return x.avg>y.avg; } int main() { int n,t;cin>>n>>t; for(int i = 1;i >a[i].m>>a[i].v; a[i].avg = a[i].v/a[i].m; } sort(a+1,a+1+n,cmp); double sum = 0; for(int i = 1;i =a[i].m) { sum = sum+a[i].v; t = t-a[i].m; } else { sum = sum+t1.0a[i].avg; break; } } cout<<fixed<<setprecision(2)<<sum; }