Codeforces Round #278 (Div. 1), problem: (A) Fight the Monster

頗有趣的題目，Greedy 亂掃

#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<cstring>
#include<vector>
#include<utility>
#include<map>
#include<set>
#include<queue>
#include<cmath>
#define INF 1000000000
using namespace std;
typedef long long int int64;
int main()
{
    int h0, a0, d0;
    int h, a, d;
    int ch, ca, cd;
    int prespend = 0;
    scanf("%d %d %d", &h, &a, &d);
    scanf("%d %d %d", &h0, &a0, &d0);
    scanf("%d %d %d", &ch, &ca, &cd);
    if(a <= d0){
        prespend = ca*(d0+1-a);
        a = d0+1;
    }
    int minspend = INF;
    for(int lx = 0; h0+2 >= a+lx-d0;lx++){
        for(int ly = 0;a0+2 >= d+ly;ly++){
            int aa = a+lx, dd = d+ly;
            int hh = (h0+aa-d0-1)/(aa-d0)*(a0-min(a0,dd));
            int dh = max(hh+1, h) - h;
            minspend = min(lx*ca + ly*cd + dh*ch + prespend, minspend);
        }
    }
    printf("%d\n", (minspend == INF) ? prespend:minspend);
    return 0;
}