[BZOJ 1033] [ZJOI2008] 杀蚂蚁antbuster 【模拟！】

题目链接： BZOJ - 1033

题目分析

模拟！纯粹按照题目描述模拟！

这是一道喜闻乐见的经典模拟题！

我一共写了2遍，Debug 历时2天的所有晚自习 ... 时间超过 8h ... 我真是太弱了啊 ...

最终对着数据和 std 终于找到错误了！

错误：好好读题！不要忽略题意中的细节！在函数中提前退出的时候想想会不会有什么事情还没有做。

Warning!Warning!Warning!

注意在给 sort 写 Cmp 的时候，一定一定一定要保证比较结果双向统一！ 若 Cmp(a, b) == false , 那么 Cmp(b, a) 一定要为 true ！！！

否则就会跪掉！一定要注意！Cmp里有一些特殊条件判断的时候一定要注意这一点！

代码

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
 
using namespace std;
 
typedef double DB; 
 
const int MaxN = 8 + 3, MaxA = 6 + 3, MaxB = 20 + 3, INF = 999999999;
const int Dx[5] = {0, 1, 0, -1}, Dy[5] = {1, 0, -1, 0};
 
int n, m, B_s, B_d, B_r, Time, Ant_Index, Target, Ant_s, Over_Time, Lev_Now;
int Msg[MaxN][MaxN], Tgt[MaxB];
 
DB Hp_Now; 
 
bool Map[MaxN][MaxN];
 
inline int gmin(int a, int b) {return a < b ? a : b;}
inline int gmax(int a, int b) {return a > b ? a : b;}
 
struct Battery
{
    int x, y;
} B[MaxB];
 
inline bool OKP(int x, int y) {
    if (x < 0 || x > n) return false;
    if (y < 0 || y > m) return false;
    return (!Map[x][y]);
}
 
struct Ant
{
    int Hp, Hp_Ceiling, Lev, Age, x, y, Lx, Ly;
    bool Alive, Cake;
     
    Ant() {
        x = y = 0;
        Lx = Ly = -1;
        Age = 0;
        Lev = Lev_Now;
        Hp = Hp_Ceiling = (int)Hp_Now;
        Alive = true; Cake = false;
    }
     
    void Move() {
        int MaxMsg = -1, nk = -1, xx, yy;
        for (int i = 0; i < 4; ++i) {
            xx = x + Dx[i]; yy = y + Dy[i];
            if (!OKP(xx, yy) || (xx == Lx && yy == Ly)) continue;
            if (Msg[xx][yy] > MaxMsg) {
                MaxMsg = Msg[xx][yy];
                nk = i;
            }
        }
        if (MaxMsg == -1) {
            Lx = x; Ly = y;
            return;
        }
        if ((Age + 1) % 5 == 0) {
            while (true) {
                nk = ((nk - 1) + 4) % 4;
                xx = x + Dx[nk]; yy = y + Dy[nk];
                if (!OKP(xx, yy) || (xx == Lx && yy == Ly)) continue;
                break;
            }
        }
        Lx = x; Ly = y;
        x += Dx[nk]; y += Dy[nk];
        Map[Lx][Ly] = false;
        Map[x][y] = true;
    }
         
    void GetCake() {
        Cake = true;
        Hp = gmin(Hp_Ceiling, Hp + (Hp_Ceiling >> 1));
    }
     
    void Print() {
        printf("%d %d %d %d %d
", Age, Lev, Hp, x, y);
    }
} A[MaxA];
 
void Init() {
    for (int i = 1; i <= 6; ++i) {
        A[i].Alive = false;
        A[i].Cake = false;
    }
    Hp_Now = 4.4; Lev_Now = 1;
    Ant_Index = 0;
    memset(Map, 0, sizeof(Map));
    for (int i = 1; i <= B_s; ++i) Map[B[i].x][B[i].y] = true;
    memset(Msg, 0, sizeof(Msg));
    Ant_s = 0;
    Target = -1;
    Over_Time = -1;
}
 
void New_Ant_Born() {
    if (Map[0][0] || Ant_s == 6) return;
    ++Ant_Index;
    if (Ant_Index == 7) {
        Ant_Index = 1;
        Hp_Now *= 1.1;
        ++Lev_Now;
    }
    A[++Ant_s] = Ant();
    Map[0][0] = true;
}
 
void Add_Message() {
    for (int i = 1; i <= Ant_s; ++i) {
        if (Target == i) Msg[A[i].x][A[i].y] += 5;
        else Msg[A[i].x][A[i].y] += 2;
    }
}
 
void Ant_Move() {
    for (int i = 1; i <= Ant_s; ++i) {
        A[i].Move();
        if (Target == -1 && A[i].x == n && A[i].y == m) {
            Target = i;
            A[i].GetCake();
        }
    }
}
 
inline int Sqr(int x) {return x * x;}
inline int Abs(int x) {return x < 0 ? -x : x;}
 
int SqrDis(int x, int y, int xx, int yy) {
    return Sqr(x - xx) + Sqr(y - yy);
}
 
int Nearest(int x, int y) {
    int MinDis = INF, Dx, ret;
    for (int i = 1; i <= Ant_s; ++i) {
        Dx = SqrDis(A[i].x, A[i].y, x, y);
        if (Dx < MinDis) {
            ret = i;
            MinDis = Dx;
        }
    }
    return ret;
}
 
bool Intersect(int x, int y, int xa, int ya, int xb, int yb) {
    if (x < gmin(xa, xb) || x > gmax(xa, xb) || y < gmin(ya, yb) || y > gmax(ya, yb)) return false;
    int S2;
    S2 = Abs(xa * yb + y * xb + x * ya - y * xa - x * yb - xb * ya);
    S2 = Sqr(S2);
    return (S2 * 4 <= SqrDis(xa, ya, xb, yb));
}
 
void Battery_Attack() {
    if (Target == -1) 
        for (int i = 1; i <= B_s; ++i) Tgt[i] = Nearest(B[i].x, B[i].y);
    else
        for (int i = 1; i <= B_s; ++i) 
            if (SqrDis(B[i].x, B[i].y, A[Target].x, A[Target].y) <= Sqr(B_r)) Tgt[i] = Target;
            else Tgt[i] = Nearest(B[i].x, B[i].y);
    for (int i = 1; i <= B_s; ++i) {
        if (SqrDis(B[i].x, B[i].y, A[Tgt[i]].x, A[Tgt[i]].y) > Sqr(B_r)) continue;
        for (int j = 1; j <= Ant_s; ++j) 
            if (Intersect(A[j].x, A[j].y, B[i].x, B[i].y, A[Tgt[i]].x, A[Tgt[i]].y)) 
                A[j].Hp -= B_d;
    }
    int Temp = 0;
    for (int i = 1; i <= Ant_s; ++i) {
        if (A[i].Hp >= 0) continue;
        A[i].Alive = false;
        Map[A[i].x][A[i].y] = false;
        if (A[i].Cake) {
            Target = -1;
            A[i].Cake = false;
        }
        ++Temp;
    }
    Ant_s -= Temp;
}
 
bool Check_Over() {
    if (Target == -1) return false;
    return (A[Target].x == 0 && A[Target].y == 0);
}
 
void Decrease_Message() {
    for (int i = 0; i <= n; ++i) 
        for (int j = 0; j <= m; ++j) 
            if (Msg[i][j] > 0) --Msg[i][j];
}
 
bool Cmp(Ant a1, Ant a2) {
    if (a1.Alive == false && a2.Alive) return false;
    if (a1.Alive && a2.Alive == false) return true;
    return a1.Age > a2.Age;
}
 
void Update_Ant() {
    sort(A + 1, A + 6 + 1, Cmp);
    for (int i = 1; i <= Ant_s; ++i) {
        ++A[i].Age;
        if (A[i].Cake) Target = i;
    }
}
 
void Print_Situation() {
    printf("%d
", Ant_s);
    for (int i = 1; i <= Ant_s; ++i) A[i].Print();
}
 
int main() 
{
    scanf("%d%d", &n, &m);
    scanf("%d%d%d", &B_s, &B_d, &B_r);
    for (int i = 1; i <= B_s; ++i) 
        scanf("%d%d", &B[i].x, &B[i].y);
    scanf("%d", &Time);
 
    Init(); 
    for (int i = 1; i <= Time; ++i) {    
        New_Ant_Born();
        Add_Message();
        Ant_Move();
        Battery_Attack();
        if (Check_Over()) {
            sort(A + 1, A + 6 + 1, Cmp);
            Over_Time = i;
            break;
        }
        Decrease_Message();
        Update_Ant();
    }
    if (Over_Time != -1) printf("Game over after %d seconds
", Over_Time);
    else printf("The game is going on
");
    Print_Situation();
    return 0;
}