HDU 3698

线段树优化DP

#include<cstdio>#include<algorithm>#define inf ((~(0U))>>1)using namespace std;typedef long long ll;int map[105][5010],c[105][5010];int dp[105][5010];struct Tree{    int l,r,min,lazy;}tree[4*5010];/*int min(int a,int b){    return a>b?b:a;}int max(int a,int b){    return a>b?a:b;}*/void build(int s,int t,int id){    tree[id].l=s,tree[id].r=t,tree[id].min=tree[id].lazy=inf;    if(s!=t){        int mid=(s+t)>>1;        build(s,mid,id<<1);        build(mid+1,t,id<<1|1);    }}void push_down(int id){    tree[id<<1].min=min(tree[id<<1].min,tree[id].lazy);    tree[id<<1].lazy=min(tree[id<<1].lazy,tree[id].lazy);    tree[id<<1|1].min=min(tree[id<<1|1].min,tree[id].lazy);    tree[id<<1|1].lazy=min(tree[id<<1|1].lazy,tree[id].lazy);    tree[id].lazy=inf;}void insert(int s,int t,int val,int id){    if(tree[id].l==s && tree[id].r==t){        tree[id].lazy=min(val,tree[id].lazy);        tree[id].min=min(tree[id].min,val);        return;    }    if(tree[id].lazy!=inf)        push_down(id);    int mid=(tree[id].l+tree[id].r)>>1;    if(t<=mid)insert(s,t,val,id<<1);    else if(s>mid)insert(s,t,val,id<<1|1);    else {        insert(s,mid,val,id<<1);        insert(mid+1,t,val,id<<1|1);    }    tree[id].min=min(tree[id<<1].min,tree[id<<1|1].min);}int query(int s,int t,int id){    if(tree[id].l==s && tree[id].r==t)        return tree[id].min;    if(tree[id].lazy!=inf)        push_down(id);    int mid=(tree[id].l+tree[id].r)>>1;    if(t<=mid)return query(s,t,id<<1);    else if(s>mid)return query(s,t,id<<1|1);    else return min(query(s,mid,id<<1),query(mid+1,t,id<<1|1));}inline void scan(int &n)//输入加速{      char cc ;      for(;cc=getchar(),cc<'0'||cc>'9';);      n=cc-'0';      for(;cc=getchar(),cc>='0'&&cc<='9';)          n=n*10+cc-'0';  }  int main(){    int i,j,n,m;    while(scanf("%d %d",&n,&m)==2){        if(n==0 && m==0)break;        for(i=1;i<=n;i++)            for(j=1;j<=m;j++)                scan(map[i][j]);        for(i=1;i<=n;i++)            for(j=1;j<=m;j++)                scan(c[i][j]);        for(i=1;i<=m;i++)            dp[1][i]=map[1][i];        for(i=2;i<=n;i++){            build(1,m,1);            for(j=1;j<=m;j++)insert(max(j-c[i-1][j],1),min(j+c[i-1][j],m),dp[i-1][j],1);            for(j=1;j<=m;j++)dp[i][j]=query(max(j-c[i][j],1),min(j+c[i][j],m),1)+map[i][j];        }        int ans=inf;        for(i=1;i<=m;i++)            ans=min(ans,dp[n][i]);        printf("%d\n",ans);    }}