#include <stdio.h>
#include <stdlib.h>
int binary_search(int n,int x,int a[]){
	int lef=0,rig=n-1;
	while(lef<=rig){
		int mid=(lef+rig)/2;
		if(a[mid]<x){
			lef=mid+1;
		}else if(a[mid]>x){
			rig=mid-1;
		}else if(a[mid]==x){
			return mid;
		}
	}
	return -1;
}
int main(void) {
	int n,x,i;
	int *a;
	int ans;
	scanf("%d %d",&n,&x);
	a=(int*)malloc(sizeof(int)*n);
	if(a==NULL){
		printf("ERROR\n");
		return 0;
	}
	for(i=0;i<n;i++){
		scanf("%d",&a[i]);
	}
	ans=binary_search(n,x,a);
	if(ans==-1){
		printf("見つかりませんでした。");
	}else{
		printf("a[%d]=%d",ans,x);
	}
 
	return 0;
}
 

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