HDU 5308 I Wanna Become A 24-Point Master（2015多校第二场）

I Wanna Become A 24-Point Master

Time Limit: 2000/1000 MS (Java/Others)    Memory
Limit: 65536/65536 K (Java/Others)

Total Submission(s): 485    Accepted Submission(s): 191

Special Judge

Problem Description

Recently Rikka falls in love with an old but interesting game -- 24 points. She wants to become a master of this game, so she asks Yuta to give her some problems to practice.



Quickly, Rikka solved almost all of the problems but the remained one is really difficult:



In this problem, you need to write a program which can get 24 points with 

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which are all equal to .

 

Input

There are no more then 100 testcases and there are no more then 5 testcases with 

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Each testcase contains only one integer 

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Output

For each testcase:



If there is not any way to get 24 points, print a single line with -1.



Otherwise, let  be
an array with 

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and at firsrt 

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You need to print  lines
and the th
line contains one integer ,
one char  and
then one integer c, where 

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"+","-","*" or "/". This line means that you let  and  do
the operation 

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store the answer into 

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If your answer satisfies the following rule, we think your answer is right:



1. 

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2. Each position of the array  is
used at most one tine.



3. The absolute value of the numerator and denominator of each element in array 

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no more than 

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Sample Input

4

 

Sample Output

1 * 2
5 + 3
6 + 4

 

Source

2015 Multi-University Training Contest 2

#include <iostream>
#include <cstring>
#include <cstdlib>
#include <cstdio>
#include <algorithm>
using namespace std;
int N;
int main()
{
    while(scanf("%d", &N)!=EOF)
    {
        if(N == 1 || N == 2 || N == 3 ) printf("-1\n");
        else if(N == 4)
        {
            printf("1 * 2\n");
            printf("5 + 3\n");
            printf("6 + 4\n");
        }
        else if(N == 5)
        {
            printf("1 * 2\n");//6  25
            printf("3 * 6\n");//7  125
            printf("7 - 4\n");//8  120
            printf("8 / 5\n");//9  24
        }
        else if(N == 6)
        {
            printf("1 * 2\n");//7  36
            printf("7 - 3\n");//8  30
            printf("8 - 4\n");//9  24
            printf("9 + 5\n");//10 30
            printf("10 - 6\n");//11 24
        }
        else if(N == 7)
        {
            printf("1 / 2\n");//8  1
            printf("3 + 8\n");//9 8
            printf("4 + 5\n");//10 14
            printf("10 + 6\n");//11 21
            printf("11 / 7\n");//12 3
            printf("12 * 9\n");//13 24
        }
        else if(N == 8)
        {
            printf("1 + 2\n");//9  16
            printf("3 + 9\n");//10 24
            printf("4 - 5\n");//11 0
            printf("11 * 6\n");//12 0
            printf("12 * 7\n");//13 0
            printf("13 * 8\n");//14 0
            printf("14 + 10\n");//15 24
        }
        else if(N == 9)
        {
            printf("1 + 2\n");//10   18
            printf("10 + 3\n");//11  27
            printf("11 * 4\n");//12  243
            printf("12 / 5\n");//13  27
            printf("6 + 7\n");//14   18
            printf("14 + 8\n");//15  27
            printf("15 / 9\n");//16  3
            printf("13 - 16\n");//17 24
        }
        else if(N == 10)
        {
            printf("1 + 2\n");//11   20
            printf("3 + 4\n");//12   20
            printf("12 + 5\n");//13  30
            printf("13 + 6\n");//14  40
            printf("14 / 7\n");//15  4
            printf("11 + 15\n");//16 24
            printf("8 - 9\n");//17   0
            printf("17 / 10\n");//18 0
            printf("16 + 18\n");//19 24
        }
        else if(N == 11)
        {
            printf("1 + 2\n");//12  22
            printf("12 / 3\n");//13 2
            printf("13 + 4\n");//14 13
            printf("14 + 5\n");//15 24
            printf("15 + 6\n");//16 35
            printf("16 + 7\n");//17 46
            printf("17 + 8\n");//18 57
            printf("18 - 9\n");//19 46
            printf("19 - 10\n");//20 35
            printf("20 - 11\n");//21 24
        }
        else if(N >= 12 && N % 2 == 0)
        {
            printf("1 + 2\n");//N+1                  2*N
            printf("%d + 3\n",N+1);//N+2             3*N
            printf("4 + 5\n");//N+3                  2*N
            printf("%d + 6\n",N+3);//N+4             3*N
            printf("%d + 7\n",N+4);//N+5             4*N
            printf("8 + 9\n");//N+6                  2*N
            printf("%d / 10\n",N+2);//N+7            3
            printf("%d / 11\n",N+5);//N+8            4
            printf("%d / 12\n",N+6);//N+9            2
            printf("%d * %d\n",N+7,N+8);//N+10       12
            printf("%d * %d\n",N+9,N+10);//N+11      24
            for(int i=0;i<(N-12)/2;i++)
            {
                printf("%d + %d\n",N+11+2*i,13+i*2);//N+12+2*i
                printf("%d - %d\n",N+12+2*i,14+i*2);//N+13+2*i
            }
        }
        else if(N>=13 && N % 2 == 1)
        {
            printf("1 + 2\n");//N+1               2*N
            printf("%d + 3\n",N+1);//N+2          3*N
            printf("4 + 5\n");//N+3               2*N
            printf("%d + 6\n",N+3);//N+4          3*N
            printf("%d + 7\n",N+4);//N+5          4*N
            printf("%d + 8\n",N+5);//N+6          5*N
            printf("%d + 9\n",N+6);//N+7          6*N
            printf("%d + 10\n",N+7);//N+8         7*N
            printf("%d + 11\n",N+8);//N+9         8*N
            printf("%d / 12\n",N+2);//N+10        3
            printf("%d / 13\n",N+9);//N+11        8
            printf("%d * %d\n",N+10,N+11);//N+12  24
            for(int i=0;i<(N-13)/2;i++)
            {
                printf("%d + %d\n",N+12+2*i,14+i*2);//N+13+2*i
                printf("%d - %d\n",N+13+2*i,15+i*2);//N+14+2*i
            }

        }
    }
}