[Usaco2017 Feb]Why Did the Cow Cross the RoadII

[题目链接]

https://www.lydsy.com/JudgeOnline/problem.php?id=4993

[算法]

动态规划

转移类似于求LCS

[代码]

#include<bits/stdc++.h>
using namespace std;
#define MAXN 1010

int n;
int a[MAXN] , b[MAXN];
int f[MAXN][MAXN];

template <typename T> inline void chkmax(T &x,T y) { x = max(x,y); }
template <typename T> inline void chkmin(T &x,T y) { x = min(x,y); }
template <typename T> inline void read(T &x)
{
    T f = ; x = ;
    char c = getchar();
    for (; !isdigit(c); c = getchar()) if (c == '-') f = -f;
    for (; isdigit(c); c = getchar()) x = (x << ) + (x << ) + c - '';
    x *= f;
}
int main()
{

        read(n);
        for (int i = ; i <= n; i++) read(a[i]);
        for (int i = ; i <= n; i++) read(b[i]);
        for (int i = ; i <= n; i++)
        {
                for (int j = ; j <= n; j++)
                {
                        if (abs(a[i] - b[j]) <= )
                                f[i][j] = f[i - ][j - ] + ;
                        else f[i][j] = max(f[i][j - ] , f[i - ][j]);
                }
        }
        printf("%d\n",f[n][n]);

        return ;

}