#include<stdio.h>
int main()
{
int count(int key,int a[],int changdu)
{
int left = 0;
int right = changdu-1;
int ret = 0;
int lim;
while (right > left)
{
lim = left+right/2;
if (a[lim]==key)
{
ret = lim;
break;
}
else if (key < a[lim])
{
left=lim+1;
}
else if (key > a[lim])
{
right= lim - 1;
}
}
return ret;
}
int run[]= {5,7,11,19,26,55,91,105,375,388};
int n=count(988,run,sizeof(run)/sizeof(run[0]));
printf("%d",n);
return 0;
}