HDOJ 1085 DP背包 水

典型的背包，不多说。

#include <iostream>
using namespace std;

const int MAX_VALUE = 1000 * (1 + 2 + 5);
int ans[MAX_VALUE + 1];

int main ()
{
    int coins[3],values[3] = {1,2,5};
    while (scanf("%d%d%d",&coins[0],&coins[1],&coins[2]) != -1)
    {
        if (coins[0] == 0 && coins[1] == 0 && coins[2] == 0)
            break;
        memset(ans,0,sizeof(ans));
        ans[0] = 1;
        int lowerBound,maxValue = 0;
        for (int i = 0;i < 3;i ++)/* 三种硬币 */
        {
            for (int j = 0;j < coins[i];j ++)/* 第i种硬币有coins[i]枚 */
            {
                if (j == 0)
                    lowerBound = values[i];
                else
                    lowerBound = maxValue;
                for (int k = maxValue + values[i];k >= lowerBound;k --)
                {
                    if (ans[k - values[i]] == 1)
                    {
                        ans[k] = 1;
                        maxValue = maxValue > k ? maxValue : k;
                    }
                }
            }
        }
        for (int i = 1; ;i ++)
        {
            if (ans[i] == 0)
            {
                printf("%d\n",i);
                break;
            }
        }
    }
    return 0;
}