Tower programming th

#include <iostream>
#include <vector>
#include <queue>
#include <stdio.h>
using namespace std;


vector<int> g[100010];
bool visited[100010];
int e[100010];

int main(){
    int k , n ,m;
    scanf("%d%d%d",&k,&n,&m);
    int u ,v;
    for(int i=1;i<=m;++i){
        scanf("%d%d",&u,&v);
        g[u].push_back(v);
    }
    queue<int> q;

    q.push(1);
    e[1]=0;
    int max1=-1e9;
    for(int i=2;i<=n;++i){
        e[i]=10000000;
    }
    while(!q.empty()){
        int y=q.front();
        q.pop();
        if(max1<y){
                max1=y;
            }
        visited[y]=true;
        if(e[y]+1<=k){
            for(auto c: g[y]){
                if(!visited[c]){
                    q.push(c);
                    visited[c]=true;
                    if(e[c]>e[y]+1){
                            e[c]=e[y]+1;
                    }
                }
            }
        }
    }



    cout << max1;

    return 0;
}