727 - Equation

[iqbal csedu]

ahhhh....alhamdulillah at last got accepted many many thanks to sazzad vai....have u got my personal message?@sazzad vai

[justcodeit]

Please help me....

I m getting runtime error in this problem

i tried eveything......
is STL allowed...

Code: Select all

#include<iostream>
#include<algorithm>
#include<stack>
using namespace std;
int main()
{
    long long t,k;
    cin>>t;
    k=t;
    getchar();
    getchar();
    while(t--)
    {
         if(t!=k-1)
             cout<<endl<<endl;
         stack<char> st;
         long long n;
         char infix;
         char postfix[51]="",infix_ex[51]="";
         long long i=0,j;
         while(1)    
         {
              infix=getchar();  
              if(infix=='\n')
                     break;     
              getchar();
              
              infix_ex[i++]=infix;
         }  
         infix_ex[i++]=')';
         n=i;
         st.push('(');
         j=0;
         for(i=0;i<n;i++)
         {
               if( infix_ex[i]=='0' || infix_ex[i]=='1' || infix_ex[i]=='2' || infix_ex[i]=='3' || infix_ex[i]=='4' || infix_ex[i]=='5' || infix_ex[i]=='6' || infix_ex[i]=='7' || infix_ex[i]=='8' || infix_ex[i]=='9' )              
               {
                      postfix[j++]=infix_ex[i];                   
               }
               if(infix_ex[i]=='('  )
               {
                      st.push('(');                     
               }
               
               if(infix_ex[i]=='*' || infix_ex[i]=='/')              
               {
                       while(st.top()=='*' || st.top()=='/')
                       {
                            char temp=st.top();
                            st.pop();                 
                            postfix[j++]=temp;
                       }
                       st.push(infix_ex[i]);
               }
               if(infix_ex[i]=='+' || infix_ex[i]=='-')              
               {
                       while(st.top()=='*' || st.top()=='/' || st.top()=='+' || st.top()=='-')
                       {
                            char temp=st.top();
                            st.pop();                 
                            postfix[j++]=temp;
                       }
                       st.push(infix_ex[i]);
               }
               if(infix_ex[i]==')'  )
               {
                      while(st.top()!='(')
                      {
                            char temp=st.top();
                            st.pop();                 
                            postfix[j++]=temp;                    
                      }     
                      st.pop();               
               }
         }
         cout<<postfix; 
    }
    return 0;
}

please help.....
thanks in advance

[brianfry713]

justcodeit, you need to check for the input terminating with end of file and print a newline after the last input.

[darkurvivor]

i've run a lot of input from forum. all the answer is the correct!
but while i submit it returns RE! plz help me to find somewhere wrong!

Code: Select all

#include <cstdio>
#include <cstdlib>
#include <fstream>
#include <iostream>
#include <string>
#include <vector>
#include <stack>
using namespace std;

int main(){

    #ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin);
    #endif

    size_t i;
    int n, run=0;
    bool first=true;
    string str;
    cin >> n;

    getchar();
    getline(cin, str);

    while(run < n){
        vector<string> eq;
        stack<char> op;

        if(!first) cout << endl;
        first=false;

        while(getline(cin, str) && str.size()!=0){
            eq.push_back(str);
        }

        for(i=0 ; i<eq.size() ; ++i){

            if(eq[i][0]=='('){
               op.push(eq[i][0]);
            }
            else if(eq[i][0]==')'){
                while(op.top()!='('){
                    cout << op.top();
                    op.pop();
                }
                op.pop();
                if(!op.empty()){
                    if(op.top()=='*'||op.top()=='/'){
                        cout << op.top();
                        op.pop();
                    }
                }
            }
            else if(eq[i][0]<='9' && eq[i][0]>='0'){
                cout << eq[i];
            }
            else{
                if(op.empty() || (!op.empty() && op.top()=='(')){
                   op.push(eq[i][0]);
                }
                else{
                    if(eq[i][0]=='+'||eq[i][0]=='-'){
                        if(op.top()=='*'||op.top()=='/'){
                            cout << op.top();
                            op.pop();
                            if(!op.empty()){
                                cout << op.top();
                                op.pop();
                            }
                        }
                        else{
                            cout << op.top();
                            op.pop();
                        }
                        op.push(eq[i][0]);
                    }
                    else if(eq[i][0]=='*'||eq[i][0]=='/'){
                        if(!op.empty() && (op.top()=='+'||op.top()=='-')){
                            op.push(eq[i][0]);
                        }
                        else{
                            cout << op.top();
                            op.pop();
                            op.push(eq[i][0]);
                        }
                    }
                }
            }
        }
        while(!op.empty()){
            cout << op.top();
            op.pop();
        }
        cout << endl;
        run++;
    }
    return 0;
}

[brianfry713]

Next time post in the existing thread. For this input:

Code: Select all

1

1
*
2
(
1
+
2
)
1
+
2

My AC code prints:

Code: Select all

1212+1*2+

[darkurvivor]

Next time post in the existing thread. For this input:

Code: Select all

1

1
*
2
(
1
+
2
)
1
+
2

My AC code prints:

Code: Select all

1212+1*2+

Sorry! I'll post in the exist thread next time.
I run your input and get another answer
but it's not the problem where it is
i found that line 66 lose a statement
while i fixed it as

Code: Select all

if(!op.empty() && op.top()!='(') 

i get AC!!

[laituanksa245]

My program passes all the test cases posted in the this forum.
However, I keep getting TLE
Can anyone give me some suggestion how to speed this up ?

Code: Select all

Code Removed
Got Ac :P

[brianfry713]

Your code is throwing a RE on the sample input.

[laituanksa245]

I think the error comes from how my program does input.
How do you recognize a blank line from the input ?

[brianfry713]

Use something like getline, gets, or fgets to read the input.

[laituanksa245]

Thanks

[hover1178]

Removed

[gr81]

getting RE, please find the code at http://ideone.com/yvuQZE

Thanks

[gr81]

will someone look into my issue...?

[lbv]

getting RE, please find the code at http://ideone.com/yvuQZE

It seems that it's possible that your oper stack gets cleared under some circumstances when it shouldn't, causing the while at line 41 to be skipped (because the stack is empty), but then you pop from oper anyway (line 46), which causes all the troubles.

Check for example this test case:

Code: Select all

1

(
5
/
3
+
5
+
0
)
-
4
*
(
2
)
*
0
/
2
-
5
*
5
/
3
/
6
*
2
+
7
-
9
-
2
/
3

Code: Select all

53/5+0+42*0*2/-55*3/6/2*-7+9-23/-