学步园

最大费用圈覆盖，转换成图的匹配来解之。

/*HDU 3722*/
#include <iostream>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <cstring>
#include <cmath>
#include <vector>
#include <queue>
#include <algorithm>
#include <map>
#include <cctype>
using namespace std;

const int maxn = 210;
const int INF = 0x3f3f3f3f;

int n, m;

int W[maxn][maxn];
int Lx[maxn], Ly[maxn];

int Left[maxn];
bool S[maxn], T[maxn];

bool match(int i)
{
    S[i] = 1;
    for(int j = 1; j <= m; j++) if(Lx[i]+Ly[j] == W[i][j] && !T[j])
    {
        T[j] = 1;
        if(!Left[j] || match(Left[j]))
        {
            Left[j] = i;
            return 1;
        }
    }
    return 0;
}

void update()
{
    int a = INF;
    for(int i = 1; i <= n; i++) if(S[i])
    for(int j = 1; j <= m; j++) if(!T[j])
        a = min(a, Lx[i]+Ly[j]-W[i][j]);
        
    for(int i = 1; i <= n; i++)
    {
        if(S[i]) Lx[i] -= a;
    }
    for(int j = 1; j <= m; j++)
    {
        if(T[j]) Ly[j] += a;
    }
}

void KM()
{
    memset(Left, 0, sizeof(Left));
    memset(Lx, 0, sizeof(Lx));
    memset(Ly, 0, sizeof(Ly));
    
    for(int i = 1; i <= n; i++)
    {
        for(int j = 1; j <= m; j++)
            Lx[i] = max(Lx[i], W[i][j]);
    }
    for(int i = 1; i <= n; i++)
    {
        for(;;)
        {
            for(int j = 1; j <= m; j++) S[j] = T[j] = 0;
            if(match(i)) break; else update();
        }
    }
}

inline void readint(int &x)
{
    char c;
    c = getchar();
    while(!isdigit(c)) c = getchar();
    
    x = 0;
    while(isdigit(c)) x = x*10+c-'0', c = getchar();
}

inline void writeint(int x)
{
    if(x > 9) writeint(x/10);
    putchar(x%10+'0');
}

char str[210][1010];

void read_case()
{
	char buf[1010];
	
	m = n;
	for(int i = 1; i <= n; i++) scanf("%s", str[i]);
}

int cal(char *fir, char *sec)
{
	int len1 = strlen(fir), len2 = strlen(sec);
	int i, j;
	for(i = len1-1, j = 0; i >= 0 && j < len2; i--, j++)
	{
		if(fir[i] != sec[j]) break;
	}
	return j;
}

void build()
{
	for(int i = 1; i <= n; i++)
	{
		for(int j = 1; j <= n; j++)
		{
			W[i][j] = cal(str[i], str[j]);
		}
		W[i][i] = 0;
	}
}

void solve()
{
	read_case();
	build();
	
	KM();
	
	int ans = 0;
	for(int i = 1; i <= m; i++) if(Left[i]) ans += W[Left[i]][i];
	printf("%d\n", ans);
}

int main()
{
	while(~scanf("%d", &n))
	{
		solve();
	}
	return 0;
}