Submission #1108238

#	Time	Username	Problem	Language	Result	Execution time	Memory
1108238		Newtonabc	Mutating DNA (IOI21_dna)	C++17	0 / 100	31 ms	4720 KiB

dna

#include "dna.h"
#include<bits/stdc++.h>
using namespace std;
const int N=1e5+10;
int prea[N],preb[N],pre[N];
void init(std::string a, std::string b) {
	int n=a.size();
	prea[0]=(a[0]=='A'),preb[0]=(b[0]=='A');
	for(int i=1;i<n;i++) prea[i]=prea[i-1]+(a[i]=='A'),preb[i]=preb[i-1]+(b[i]=='A');
	pre[0]=(a[0]!=b[0]);
	for(int i=1;i<n;i++) pre[i]=pre[i-1]+(a[i]!=b[i]);
	/*for(int i=0;i<n;i++) cout<<pre[i] <<" ";
	cout<<'\n';*/
}

int get_distance(int x, int y) {
	if(prea[y]-prea[x]==prea[y]-prea[x]) return (pre[y]-(x-1>=0?pre[x-1]:0))/2;
	return -1;
}

Compilation message (stderr)

dna.cpp: In function 'int get_distance(int, int)':
dna.cpp:17:20: warning: self-comparison always evaluates to true [-Wtautological-compare]
   17 |  if(prea[y]-prea[x]==prea[y]-prea[x]) return (pre[y]-(x-1>=0?pre[x-1]:0))/2;
      |     ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 21
• Subtask 2: 0 / 22
• Subtask 3: 0 / 13
• Subtask 4: 0 / 28
• Subtask 5: 0 / 16