负载均衡的算法有哪些_acwing是什么

输入样例：
5
17 9 14 16 4
输出样例：
11

#include<bits/stdc++.h>
using namespace std;
const int N = 110;
const int M = 4 * (50 * 50 + 400);
const int INF = 0x3f3f3f3f;
int n,m,s,e;
struct Edge{ 
   
    int v,next,w,f;
}edge[M];
int head[N],cnt = 0;
void add(int u,int v,int f,int w){ 
   
    edge[cnt].v = v;
    edge[cnt].w = w;
    edge[cnt].f = f;
    edge[cnt].next = head[u];
    head[u] = cnt ++;
}
int w[N];
int q[N],hh = 0,tt = 0,pre[N],curf[N],st[N],d[N];
bool spfa(){ 
           //最大流最大费用的话就求最长路即可
    memset(d,0x3f,sizeof d);
    memset(curf,0,sizeof curf);
    memset(st,0,sizeof st);
    hh = tt = 0;
    d[s] = 0,q[tt ++] = s,curf[s] = INF;
    st[s] = true;
    while(hh != tt){ 
   
        int t = q[hh ++];
        if(hh == N)hh = 0;
        st[t] = false;
        for(int i = head[t];~i;i = edge[i].next){ 
   
            int v = edge[i].v,w = edge[i].w;
            if(edge[i].f && d[v] > d[t] + w){ 
   
                d[v] = d[t] + w;
                pre[v] = i;
                curf[v] = min(edge[i].f,curf[t]);
                if(!st[v]){ 
   
                    q[tt ++] = v;
                    if(tt == N)tt = 0;
                    st[v] = true;
                }
            }
        }
    }
    return curf[e] > 0;
}
void EK(int &flow,int &cost){ 
   
    flow = cost = 0;
    while(spfa()){ 
   
        int t = curf[e];
        flow += t;cost += t * d[e];
        for(int i = e;i != s;i = edge[pre[i] ^ 1].v){ 
   
            edge[pre[i]].f -= t,edge[pre[i] ^ 1].f += t;
        }
    }
}
int main(){ 
   
    cin>>n;
    s = 0,e = n + 1;
    int x;
    memset(head,-1,sizeof head);
    int res = 0;
    for(int i = 1;i <= n;i ++){ 
   
        cin>>w[i];
        res += w[i];
    }
    int _x = res / n;
    for(int i = 1;i <= n;i ++){ 
   
        if(w[i] > _x){ 
   
            add(s,i,w[i] - _x,0);
            add(i,s,_x - w[i],0);
            for(int j = 1;j <= n;j ++){ 
   
                int t = min(abs(i - j),n - abs(i - j));
                add(i,j,INF,t);
                add(j,i,0,-t);
            }
        }
        else { 
   
            add(i,e,_x - w[i],0);
            add(e,i,w[i] - _x,0);
        }
    }
    int flow = 0,cost = 0;
    EK(flow,cost);
    cout<<cost<<endl;
    return 0;
}