hdu 4445 Crazy Tank（枚举）

标签：枚举

http://acm.hdu.edu.cn/showproblem.php?pid=4445

要求发射的炮弹在都不落在friendly tank区域的条件下落在enemy tank区域的最多数目。

直接暴力枚举角度。。

#include <stdio.h>
#include <iostream>
#include <map>
#include <set>
#include <bitset>
#include <list>
#include <stack>
#include <vector>
#include <math.h>
#include <string.h>
#include <queue>
#include <string>
#include <stdlib.h>
#include <algorithm>
//#define LL __int64
#define LL long long
#define eps 1e-9
const double PI = acos(-1.0);
const double g = 9.8;
using namespace std;

int n;
double l1,r1,l2,r2,h;
double v[210];

int solve(double a)
{
    int cnt = 0;
    for(int i = 0; i < n; i++)
    {
        double Vy0 = v[i] * sin(a);
        double Vx0 = v[i] * cos(a);
        double Vy = sqrt(Vy0*Vy0 + 2*g*h);
        double t = (Vy - Vy0)/g;
        double s = t*Vx0;
        if(s >= l2 && s <= r2)
            return 0;
        if(s >= l1 && s <= r1)
            cnt++;
    }
    return cnt;
}

int main()
{
    while(~scanf("%d",&n)&&n)
    {
        scanf("%lf %lf %lf %lf %lf",&h,&l1,&r1,&l2,&r2);
        for(int i = 0; i < n; i++)
            scanf("%lf",&v[i]);

        double add = PI/1000.0;
        int ans = 0;
        for(double i = -PI/2; i <= PI/2; i += add)
        {
            ans = max(ans,solve(i));
        }
        printf("%d\n",ans);
    }
    return 0;

}

hdu 4445 Crazy Tank（枚举）

标签：枚举

原文地址：http://blog.csdn.net/u013081425/article/details/40926449