Cant find the values I stored into a map - c++

Question

I'm basically reading a file character by character, and when I encounter a new number I store it in a std::map as a key with the element equal to 1. The more times I encounter the same number, I increment that key's element:
if(intMap.count(singleCharacter)){
//keyexist just increment count else
//cout<<"exist"<<endl;
int newValue = intMap.at(singleCharacter) + 1; //grabs the value that already exists and we need to incrmenet it by 1 and store the new value in the map.
std::map<int, int>::iterator it = intMap.find(singleCharacter); //finds the single character and increments it by 1.
if (it != intMap.end())
it->second = newValue; //setting the new increment value into the element
}else{
//doesnt exist and and we need to create it and incrmenet by 1
//cout<<"doesnt exist"<<endl;
intMap.insert(pair<int, int>(singleCharacter,1));
cout<<singleCharacter <<" new made : "<<intMap.at(singleCharacter) <<endl;
}
}
for (auto& p : intMap ) {
cout << p.first<<": "<< p.second <<endl;; // "Karl", "George"
}
The only problem is, when I try to print out all of the values in the map, it gives me random numbers, and I don't understand where they are coming from.
This the file that I'm reading:
An International Standard Book Number (ISBN) is a code of 10 characters, referred to as ISBN-10,
separated by dashes such as 0-7637-0798-8. An ISBN-10 consists of four parts: a group code, a publisher code,
a code that uniquely identifies the book among those published by a particular publisher, and a check character.
The check character is used to validate an ISBN. For the ISBN 0-7637-0798-8, the group code is 0,
which identifies the book as one from an English-speaking country. The publisher code 7637 is for "Jones and Bartlett Publishers
The output I'm getting:
48: 8
49: 3
51: 3
54: 3
55: 8
56: 4
57: 2
The output I should be getting should be like:
1: and the amount of times it was seen
That goes the same for any number.

Answer 1

You get those "random" numbers because you are using std::map<int,int> instead of std::map<char,int>. What you get printed are the ASCII numeric codes for character symbols, and their counts.
So, you need to either change the map's type, or cast the keys back to char:
for (auto& p : intMap ) {
cout << static_cast<char>(p.first) << ": "<< p.second <<endl;
}
Note: std::map::operator[] is precisely designed for such case, it will initialize missed values with 0 in this case, so all of your conditions can be replaced with:
intMap[singleCharacter]++;
Details can be found in this documentation.