密码机

Posted 2021-01-04 wjnclln

树状数组

#include<bits/stdc++.h>

using namespace std;

int x,y,c[200005];

char str[20];

int inline read(){

int x=0,f=1;

char ch=getchar();

while(ch<‘0‘||ch>‘9‘)

ch=getchar();

while(ch>=‘0‘&&ch<=‘9‘){

x=x*10+ch-‘0‘;

ch=getchar();

}

return x*f;

}

inline void add(int x,int y){

while (x<=20005){

c[x]^=y;

x+=x&-x;

}

return;

}

inline int ask(int x){

int sum=0;

while (x){

sum^=c[x];

x-=x&-x;

}

return sum;

}

int main(){

while (~scanf("%s",str)){

if (str[0]==‘A‘||str[0]==‘R‘){

x=read();

add(x,x);

}

else if (str[0]==‘X‘){

x=read();

y=read();

if (x>y)

printf("0 ");

else

printf("%d ",ask(x-1)^ask(y));

}

else return 0;

scanf(" ");

}

return 0;

}