HDU - 6804 Contest of Rope Pulling

传送门：HDU - 6804

思路分析

将B组的重量改为相反数，问题就转化为01背包问题，答案是重量为0的最大价值
因为值域可能会很大，考虑将数组随机，值域就会减小

AC代码

#pragma GCC optimize("Ofast,no-stack-protector")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#include <bits/stdc++.h>
#define fi first
#define se second
#define ll long long
#define pb push_back
#define mp make_pair
#define fun function
#define sz(x) (x).size()
#define lowbit(x) (x)&(-x)
#define all(x) (x).begin(),(x).end()
#define mem(a,b) memset(a,b,sizeof(a))

namespace FastIO {
#define BUF_SIZE 100000
#define OUT_SIZE 100000
    bool IOerror=0;
    inline char nc() {
        static char buf[BUF_SIZE],*p1=buf+BUF_SIZE,*pend=buf+BUF_SIZE;
        if(p1==pend) {
            p1=buf;
            pend=buf+fread(buf,1,BUF_SIZE,stdin);
            if(pend==p1) {
                IOerror=1;
                return -1;
            }
        }
        return *p1++;
    }
    inline bool blank(char ch) {
        return ch==' '||ch=='\n'||ch=='\r'||ch=='\t';
    }
    template<class T> inline bool read(T &x) {
        bool sign=0;
        char ch=nc();
        x=0;
        for(; blank(ch); ch=nc());
        if(IOerror)return false;
        if(ch=='-')sign=1,ch=nc();
        for(; ch>='0'&&ch<='9'; ch=nc())x=x*10+ch-'0';
        if(sign)x=-x;
        return true;
    }
    template<class T,class... U>bool read(T& h,U&... t) {
        return read(h)&&read(t...);
    }
#undef OUT_SIZE
#undef BUF_SIZE
};
using namespace std;
using namespace FastIO;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int INF = 0x3f3f3f3f;
const int base=1e6;
const int ch=150000;

ll dp[base+ch*3];

struct node{
    int w,v;
}a[3000];

#define re register

int main() {

#ifdef xiaofan
    freopen("1.in","r",stdin);
    freopen("1.out","w",stdout);
#endif

    int T;
    read(T);
    while(T--){
        int n,m;
        read(n,m);
        for(re int i=1;i<=n+m;++i){
            read(a[i].v,a[i].w);
            if(i>n) a[i].v=-a[i].v;
        }
        n+=m;
        for(re int i=base-ch;i<=base+ch;++i) dp[i]=-1e18;
        random_shuffle(a+1,a+1+n);
        random_shuffle(a+1,a+1+n);
        dp[base]=0;
        for(re int i=1;i<=n;i++){
            if(a[i].v>=0){
                for(int j=base+ch;j>=base-ch+a[i].v;j--) dp[j]=max(dp[j],dp[j-a[i].v]+a[i].w);
            }else{
                for(int j=base-ch;j<=base+ch-a[i].v;j++) dp[j]=max(dp[j],dp[j-a[i].v]+a[i].w);
            }
        }
        printf("%lld\n",dp[base]);
        
    }




    return 0;
}