Whats wrong with this code? (BINADD)

#1

Problem:

#include<bits/stdc++.h>
using namespace std;
int check(string &a, string &b){
while(a.size()<b.size()) a += ‘0’;
while(a.size()>b.size()) b += ‘0’;
a += ‘0’, b += ‘0’;
int carry = 0, k = 0, ans = 0;
bool flag = false;
for(int i=a.size()-1; i>=0; i–){
if(a[i] == ‘1’ && b[i] == ‘1’){
// Carry genration
if(flag)
k = 0;
flag = true;
}
else if((a[i]== ‘0’ && b[i] == ‘1’) || (a[i] == ‘1’ && b[i] == ‘0’)){
// Carry propogation
if(flag)
k++;
}
else{
flag = false;
k = 0;
}
ans = max(ans, k);
}
return ans + 1;
}
int main(){
int t;
cin >> t;
while(t–){
string a, b;
cin >> a >> b;
if(count(b.begin(), b.end(), ‘0’) == b.length()){
cout << 0 << endl;
continue;
}
reverse(a.begin(), a.end());
reverse(b.begin(), b.end());
cout << check(a, b) << ‘\n’;
}
}

#2

Please either format your code or link to your submission - the forum software has mangled it and it won’t compile! :slight_smile:

#3

https://www.codechef.com/viewsolution/28385052

#4 
public static void main (String[] args) throws java.lang.Exception
{
	// your code goes here
	Scanner in=new Scanner(System.in);
	int t = in.nextInt();
	in.nextLine();
	for(int i=0;i<t;i++) {
	    String s1=in.nextLine();
	    String s2=in.nextLine();
	    int a=Integer.parseInt(s1,2);
	    int b=Integer.parseInt(s2,2);
	    
	    int count=0;
	    while (b>0) {
	        int u=a;
	        a=a^b;
	        b=2*(u&b);
	        count++;
	    }
	    System.out.println(count);
	}
}

This is how I did it. Although I only got 20 points.

#5

That’s just plain brute Force lol

#6

when you add leading zeros to one of the strings to make them equal size you add them in the end of the string insted of the beginning

#7

Thanks mate! Didn’t notice that

#8

Also, please refrain from using a = ‘0’+a multiple times, as the + operator takes linear time, you would end up getting a ‘TLE’. I would recommend using resize or something similar.