#include<bits/stdc++.h>using namespace std; inline long long read() {     long long f=1,ans=0;char c;     while(c<'0'||c>'9'){if(c=='-')f=-1;c=getchar();}     while(c>='0'&&c<='9'){ans=ans*10+c-'0';c=getchar();}     return f*ans; } long long a,b; long long deep; long long x[1001]; long long cx(double x) {     if(int(x)==x) return int(x);     return int(x)+1; } long long gcd(long long a,long long b) {     if(b==0) return a;     return gcd(b,a%b); } bool f=false; long long xx[1001]; void dfs(long long be,long long ans,long long fz,long long fm) {     if(fz<0) return;     if(fm==0) return;     if(ans==deep)     {                  if(fz-fm==0||fz==
                        
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