Flash memory

input/code.cpp: In function 'void decode()':
input/code.cpp:59:13: warning: unused variable 'ans' [-Wunused-variable]
   59 |         int ans = 0;
      |             ^~~

#include <bits/stdc++.h>

#define debug(x) cout << #x << ": " << x << "\n"
#define all(x) x.begin(), x.end()

using namespace std;
using ll = long long;

const int N = 101;
const int M = 101;
const int inf = 1e9;
const ll LLinf = 1e16;


void encode(){

    int b, m;
    cin >> b >> m;

    while(1){
        int c;
        cin >> c;
        if(c == 0)exit(0);

        string s; cin >> s;
        string val; cin >> val;

        int start = 0;
        for(int i = 0; i < b/2; ++i){
            if(s[i] == '1')start = b/2;
        }
        if(start != 0){
            bool need_new = 0;
            for(int i = start; i < b; ++i){
                if(s[i] == '1')need_new = 1;
            }
            if(need_new){
                cout << 0 << endl;
                continue;
            }
        }
        for(int i = 0; i < m; ++i){
            s[i+start] = val[i];
        }
        cout << s << endl;
    }
}

void decode(){

    int b, m;
    cin >> b >> m;
    
    while(1){
        int c;
        cin >> c;
        if(c == 0)exit(0);
        string s; cin >> s;
        int ans = 0;

        bool zero = 1;
        for(int i = 0; i < b; ++i){
            if(s[i] == '1')zero = 0;
        }

        if(zero){
            cout << string(m, '0') << endl;
            continue;
        }

        int start = 0;
        for(int i = b/2; i < b; ++i){
            if(s[i] == '1')start = b/2;
        }

        string ret = "";
        for(int i = start; i < start + m; ++i){
            ret += string(1, s[i]);
        }
        cout << ret << endl;
    }
}

int main(){

    int t;
    cin >> t;
    if(t == 1)encode();
    else decode();


}

Test 1

Verdict: RUNTIME ERROR

Test 2

Verdict: RUNTIME ERROR

Test 3

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Test 4

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Test 5

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Test 6

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Test 7

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Test 8

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Test 9

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Test 10

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Test 11

Verdict: RUNTIME ERROR

Test 12

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Test 13

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Test 14

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Test 15

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Test 16

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Test 17

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Test 18

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Test 19

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Test 20

Verdict: TIME LIMIT EXCEEDED