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字数统计: 387 字

题目地址

题解

水DP。
按照时间变化递推即可。

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#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <cstring>
#include <cctype>
#define INF 2000000000
using namespace std;
typedef long long ll;
int read(){
    int f=1,x=0;char c=getchar();
    while(c<'0'||c>'9'){if(c=='-')f=-f;c=getchar();}
    while(c>='0'&&c<='9')x=x*10+c-'0',c=getchar();
    return f*x; 
}
int n,m,pos1[1005][2],pos2[1005][2],f[1005][1005];
char s1[1005],s2[1005];
void movement(char c,int &x,int &y){
    if(c=='N')y++;if(c=='S')y--;
    if(c=='E')x++;if(c=='W')x--;
}
int sqr(int a,int b){
    return (pos1[a][0]-pos2[b][0])*(pos1[a][0]-pos2[b][0])+
    (pos1[a][1]-pos2[b][1])*(pos1[a][1]-pos2[b][1]);
}
void init(){
    n=read(),m=read();
    pos1[0][0]=read(),pos1[0][1]=read();
    pos2[0][0]=read(),pos2[0][1]=read();
    scanf("%s%s",s1+1,s2+1);
    for(int i=1,x=pos1[0][0],y=pos1[0][1];i<=n;i++)
        movement(s1[i],x,y),
        pos1[i][0]=x,pos1[i][1]=y;
    for(int i=1,x=pos2[0][0],y=pos2[0][1];i<=m;i++)
        movement(s2[i],x,y),
        pos2[i][0]=x,pos2[i][1]=y;
}
void solve(){
    memset(f,0x14,sizeof(f));
    f[0][0]=0;
    for(int i=1;i<=n;i++)
        f[i][0]=f[i-1][0]+sqr(i,0);
    for(int i=1;i<=m;i++)
        f[0][i]=f[0][i-1]+sqr(0,i);
    for(int i=1;i<=n;i++)
        for(int j=1;j<=m;j++)
            f[i][j]=min(f[i-1][j],f[i][j-1]),
            f[i][j]=min(f[i][j],f[i-1][j-1]),
            f[i][j]+=sqr(i,j);
    printf("%d\n",f[n][m]);
}
int main(){
    init();
    solve();
    return 0;
}

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