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codechef practice problem

this my code for FLOW004 in codechef easy sections PLz see I tested with many inputs and got desired output but it is showing wrong plz guide

#include <iostream>

using namespace std;

int main() { int T; cin>>T; while(T>0){ int N,a; cin>>N;

    int b=0;
   else {

    for (int P=100;N%P!=N;P=P*10){
        int c=N-N%P;


// your code goes here
return 0;


Asked by: aj.20u10739 on Sept. 14, 2021, 3:34 p.m. Last updated on Sept. 14, 2021, 3:34 p.m.

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1 Answer(s)


Your first if condition is slightly incorrect.
You've tried to keep b=N/10 for N<100 but, let's consider N=4. The sum should be 8. But your code will return 4.

But notice that you can actually cover these cases in your for loop only.
Consider the following structure of your main function.

int b=a;
for (int P=10;N%P!=N;P=P*10){
    int c=N-N%P;


You first initialize the value of b by a only to cover the case when N is single digit. Then you start the value of P by 10 to cover all the digits starting from the digit at tens place. In this way you'll achieve correct answer.

mahawarvishal10 last updated on Sept. 15, 2021, 12:51 a.m. 0    Reply    Upvote   


thank you very much

aj.20u10739 last updated on Sept. 15, 2021, 10:06 a.m.

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