Submission #1680302

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Source Code Expand

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>
#include <math.h>
#include <vector>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <string>
#include <iostream>
#include <algorithm>
using namespace std;

#define getmid(l,r) ((l) + ((r) - (l)) / 2)
#define MEM(a,b) memset(a,b,sizeof(a))
#define MP(a,b) make_pair(a,b)
#define PB push_back

typedef long long ll;
typedef pair<int,int> pii;
const double eps = 1e-8;
const int INF = (1 << 30) - 1;

ll N,A;

ll Q_pow(ll x,ll y){
	ll res = 1;
	while(y){
		if(y & 1) res = res * x;
		x = x * x;
		y >>= 1;
	}
	return res;
}

ll Cal(ll num,ll v){
	ll t = v / num;
	if(t > pow(N,1.0 / num)){
		return A * num + v + 1;
	}
	ll qp = Q_pow(t,num - 1);
	ll mul = num == 1 ? v : qp * (v - qp);
	return A * num + v + N / mul + (N % mul ? 1 : 0);
}

int main(){
	scanf("%lld%lld",&N,&A);
	ll ans = N;
	ll top = 100000;
	if(N <= top) top = N;
	for(ll i = 1; i <= top; ++i){
		ll l = i,r = N;
		while(l + 1 < r){
			ll mid1 = (l + r) / 2,mid2 = (mid1 + r) / 2;
			ll r1 = Cal(i,mid1);
			ll r2 = Cal(i,mid2);
			//printf("A %lld -> %lld ,,, %lld -> %lld\n",mid1,r1,mid2,r2);
			if(r1 < r2){
				r = mid2;
			}
			else{
				l = mid1;
			}
		}
		ll res = Cal(i,l);
		//printf("B %lld %lld %lld -- %lld\n",i,l,r,res);		
		for(ll j = l + 1; j <= r; ++j) res = min(res,Cal(i,j));
		//if(res > ans) break;
		//printf("%lld , res ; %lld\n",i,res);
		ans = min(ans,res);
	}
	printf("%lld\n",ans);
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:49:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld%lld",&N,&A);
                         ^

Judge Result