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Decryption

TIME LIMIT = 1 SEC.

All sensitive messages in this world are encrypted. This is nothing new. Encryption has been an important part of communication since the times of Julius Caesar. Let's try to crack a simple encrypted message. Lucky for us, C.H.R.I.S. has told us the encryption algorithm. It's pretty simple: It is the letter followed by the number of times that letter occurs.

Input	Output
First line will contain L - the number of characters in the encrypted message. The second line will contain the encrypted message itself.	For each testcase, output the decrypted message.

Constraints

1 ≤ L ≤ 1000

Example Test Case

Input	Output
6 a1b2c3	abbccc

Solution

#include <iostream> #include <string> #include <cctype> using namespace std; int main() { int n,i,t,j,last_char; string temp; cin>>n; //take n string ip; cin>>ip; //take the encrypted text for(i=0;i<n;i++) { if(isalpha(ip[i])) //if current character is alphabet, set last_char to index of that alphabet last_char=i; else if(isdigit(ip[i])) //if is digit, make a number from all the digits starting from that digit { //first collect all the digits and make a string number j=i; while(isdigit(ip[j])) { temp += ip[j]; j++; } i=j-1; //convert that string number to an actual number. j = stoi(temp); //print the last character j number of times. while(j--) cout<<ip[last_char]; temp.clear(); //clear that temp string number. } } return 0; }