Why am i getting an infinite loop in this approach

#1

int main() {
int t;
cin>>t;
while(t–)
{
string s;
cin>>s;
map<string,int>freq;
map<string,int>::iterator it;
for(int i=0;i<s.size();i++)
{
string p="\0";
p=p+s[i];
if(freq.find§==freq.end())
freq[p]=1;
for(it=freq.begin();it!=freq.end();it++)
{
string b=(it->first)+p;
if(freq.find(b)==freq.end())
freq[b]=1;
}
}
cout<<freq.size()<<endl;
}
}

#2

While iterating the map, you are also inserting values in the map, which results in an infinte loop.

#3

how can i correct this?

#4

@neha_153 This approach won’t work because the no of subsequence are so large that you cannot generate all the subsequences.
Here have a look at my code. You have to calculate all the distinct subsequences without generating them.

#5

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