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help to find error

Joseph huho (1)
please help to fint where the error is in this code i want the function to display the bigger number among the one there in the program
#include <iostream>
using namespace std;
int max(int a,intb)
{
int a=100;
int b=200;
int ret;
ret= max(a,b);
return ret;
}
int main()
{
int result;
if(a>b)
result=a;
{
cout<<"The answer is"<< result<<endl;
}
else
result=b;
{
cout<<"The answer is"<< result <<endl;
return 0;
}
}
vlad from moscow (6539)
Please, read the compiler error messages and try to update your program yourself. I think that the compiler already pointed out undeclared identifier intb
Last edited on
Sucho (26)
You have written the function, but for it to work, you must call it! Use this code-
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#include<iostream>
using namespace std;
int max(int a,int b)
{
if(a>b)
    return a;
else if(a<b)
    return b;
}
int main()
{
int c=0,d=0,e=0;
cout<<"Enter first number";
cin>>c;
cout<<"\n Enter second number";
cin>>d;
e=max(c,d);
cout<<"The answer is"<< e<<endl;
return 0;
}
vlad from moscow (6539)
@Sucho


Your code has undefined behavior because function max returns nothing in the case of a == b
Last edited on
Sucho (26)
Then use this-
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#include<iostream>
using namespace std;
int max(int a,int b)
{
if(a>b)
    return a;
else if(a<b)
    return b;
else if(a==b)
    return 1;
}
int main()
{
int c=0,d=0,e=0;
cout<<"Enter first number";
cin>>c;
cout<<"\n Enter second number";
cin>>d;
e=max(c,d);
if(e!=1)
      cout<<"The answer is"<< e<<endl;
else
      cout<<"The Entered numbers are same";
return 0;
}
Last edited on
vlad from moscow (6539)
@Sucho


This function definition is invalid
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int max(int a,int b)
{
if(a>b)
    return a;
else if(a<b)
    return b;
else if(a==b)
    return 1;
}


because its return value 1 is ambiguios. It is not clear whether a == b or the maximum is equal to 1.

The correct function definition will look as

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int max( int a, int b )
{
   return ( ( a < b ) ? b : a );
}

Sucho (26)
Yup, I get your point. Foolishly overlooked that. But in your code what will it be if a==b? and moreover i can change my code which will work. Ckeck it out-
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#include<iostream>
using namespace std;
int max(int a,int b)
{
if(a>b)
    return a;
else if(a<b)
    return b;
else if(a==b)
    return (a+b);
}
int main()
{
int c=0,d=0,e=0;
cout<<"Enter first number";
cin>>c;
cout<<"\n Enter second number";
cin>>d;
e=max(c,d);
if(e!=c+d)
      cout<<"The answer is"<< e<<endl;
else
      cout<<"The Entered numbers are same";
return 0;
}

The returned value will never be maximum as the return value changes according to the entered numbers. What do u say @vlad?
vlad from moscow (6539)
Well. how do you determine that a is equal to b? You will use the expression

max( a, b ) == a + b;

This expression looks very strange and only confuses a user.

As for the code I suggested all is simple

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if ( a == b )
{
   std::cout << "a and b are equal each other" << std::endl;
}
else
{
   ats::cout << "the maximum is equal to " << max( a, b ) << std::endl;
}
Last edited on
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