Holding Bin-Laden Captive!
http://acm.hdu.edu.cn/showproblem.php?pid=1085
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 7135 Accepted Submission(s): 3143
“Oh, God! How terrible! ”

Don’t be so afraid, guys. Although he hides in a cave of Hang Zhou, he dares not to go out. Laden is so bored recent years that he fling himself into some math problems, and he said that if anyone can solve his problem, he will give himself up!
Ha-ha! Obviously, Laden is too proud of his intelligence! But, what is his problem?
“Given some Chinese Coins (硬币) (three kinds-- 1, 2, 5), and their number is num_1, num_2 and num_5 respectively, please output the minimum value that you cannot pay with given coins.”
You, super ACMer, should solve the problem easily, and don’t forget to take $25000000 from Bush!
1 1 3 0 0 0
4
解法一(这个是网上找的,很犀利,我佩服的五体投地):
直接找规律搞定!!!
# include <iostream>
using namespace std;
int main()
{
int num1,num2,num5;
while(cin>>num1>>num2>>num5 && (num1 || num2 || num5))
{
if(num1==0)
cout<<1<<endl;
else if(1*num1+2*num2>=4)
cout<<1*num1+2*num2+5*num5+1<<endl;
else
cout<<1*num1+2*num2+1<<endl;
}
return 0;
}
解法二(母函数):
#include<iostream>
using namespace std;
int main(){
int num_1,num_2,num_5,num,i,j,k;
int c[8005],temp[8005];
while(scanf("%d%d%d",&num_1,&num_2,&num_5)!=EOF&&(num_1||num_2||num_5) ){
num=num_1*1+num_2*2+num_5*5;
for( i=0;i<=num;i++){ //初始化
c[i]=0;
temp[i]=0;
}
//第一个表达式和第二个表达式相乘
for( i=0;i<=num_1;i++) //用第一个表达式表(即面值为1的硬币)表达所有的面值都只有一种情况
c[i]=1;
for( j=0;j<=num_1*1;j++)
for( k=0;k<=num_2*2;k+=2)
temp[j+k]+=c[j];
for( j=0;j<=num_1*1+num_2*2;j++){//扩大面值范围
c[j]=temp[j];
temp[j]=0;
}
//第二个表达式和第三个表达式相乘
for( j=0;j<=num_1*1+num_2*2;j++)
for( k=0;k<=num_5*5;k+=5)
temp[j+k]+=c[j];
for( j=0;j<=num;j++){ //扩充范围
c[j]=temp[j];
temp[j]=0;
}
for( i=0;i<=num;i++) //查找第一个为0的数
if(c[i]==0){
break;
}
printf("%d\n",i); //不知道是什么原因,这个放在if(c[i]==0) 里面是WA的 ,估计是HDOJ的系统问题
}
return 0;
}