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/*
  Copyright 2011 Marek "p2004a" Rusinowski
  Binary search
*/
#include <cstdio>
 
#define MAXN 1000000
 
int array[MAXN];
 
int pos(int *begin, int *end, int a) {
  int *old_begin = begin, *center = NULL;
  while (begin + 1 < end) {
    center = (end - begin) / 2 + begin;
    if (*center < a) {
      begin = center;
    } else if (*center > a) {
      end = center;
    } else {
      return center - old_begin;
    }
  }
  return begin - old_begin;
}
 
int main() {
  int n, a;
  scanf("%d", &n);
  for (int i = 0; i < n; ++i) {
    scanf("%d", &array[i]);
  }
  scanf("%d", &a);
  printf("%d\n", pos(array, array + n, a) + 1);
  return 0;
}
 

prog.cpp: In function ‘int main()’:
prog.cpp:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result
prog.cpp:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result
prog.cpp:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result

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