Following are some ways to find the reverse of a number (also removes extra zeroes at beginning of reversed number)
Using while loop:
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6 | while(n)
{
ans *= 10;
ans += n% 10;
n /= 10;
}
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Using built in function in C++
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3 | string s=to_string(n);
reverse(s.begin(),s.end());
int reversed_n= stoi(s);
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Long way :
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34 | int rev(int n)
{
int ans=0;
vector<int> v;
while(n>0)
{
v.push_back(n%10);
n /=10;
}
int i=0;
for(int p:v)
{
if(p==0) i++;
else break;
}
int m=1;
for(int p=v.size()-1;p>=i;p--)
{
v[p] *=m;
m *=10;
ans+=v[p];
}
return ans;
}
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Using Stack:
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24 | int n=234;
stack<int> st;
while (n != 0)
{
st.push(n % 10);
n /= 10;
}
int reversed_n = 0;
int i = 1;
while (!st.empty())
{
reversed_n +=(st.top() * i);
st.pop();
i *= 10;
}
cout<<reversed_n;
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