Google Interview Question
Web:
www.google.com
|
HQ:
Mountain View, CA
Overview |
| |
Salaries |
| |
Reviews |
| |
Interviews |
| |
Photos |
| |
Jobs |
| |
|
1,223 Interview Reviews |
Back to all Google Interview Questions & Reviews
Interview questions and reviews posted anonymously by interview candidates
Interview Question for Software Engineer at Google:
Jan 31, 2012
1 of
1 people found this helpful
If you have an unsorted array of numbers from 1-100, except 1 of those numbers is missing, how do you determine which number is missing
Add Tags
[?]
Helpful Question?
Yes |
No
Inappropriate?
Answers & Comments (7)
2 of 3 people found this helpful
Feb 2, 2012
100*(100-1)/2 - sum(array)
Helpful Answer?
Yes |
No
Inappropriate?
0 of 3 people found this helpful
Feb 8, 2012
public int getMissing(int[] values){
if(values.length == 0 || values == null)
return -1;
for(int 1 : values){
for(int x = 1; x <= 100; x++){
if(!values.contains(x))
return x;
}
}
return 0;
}
if(values.length == 0 || values == null)
return -1;
for(int 1 : values){
for(int x = 1; x <= 100; x++){
if(!values.contains(x))
return x;
}
}
return 0;
}
Helpful Answer?
Yes |
No
Inappropriate?
0 of 2 people found this helpful
Feb 13, 2012
public int missing(int array[])
{
int missingNum = 0,i;
for(i =1;i<=array.length+1;i++)
{
missingNum = missingNum^i;
}
for(i =0;i<array.length;i++)
{
missingNum = missingNum^array[i];
}
return missingNum;
}
{
int missingNum = 0,i;
for(i =1;i<=array.length+1;i++)
{
missingNum = missingNum^i;
}
for(i =0;i<array.length;i++)
{
missingNum = missingNum^array[i];
}
return missingNum;
}
Helpful Answer?
Yes |
No
Inappropriate?
4 of 4 people found this helpful
Feb 18, 2012
The summation formula presented by DM is incorrect. It should be (100)*(100+1)/2
Helpful Answer?
Yes |
No
Inappropriate?
1 of 1 people found this helpful
Mar 4, 2012
fastest solution is to XOR everything
Helpful Answer?
Yes |
No
Inappropriate?
Apr 25, 2012
import random
def find_missing_number(arr):
bits = len(arr)+1
for i, v in enumerate(arr):
bits ^= v ^ i+1
return bits
numbers = range(1, 101)
random.shuffle(numbers)
print find_missing_number(numbers[:-1]), "==", numbers[-1]
def find_missing_number(arr):
bits = len(arr)+1
for i, v in enumerate(arr):
bits ^= v ^ i+1
return bits
numbers = range(1, 101)
random.shuffle(numbers)
print find_missing_number(numbers[:-1]), "==", numbers[-1]
Helpful Answer?
Yes |
No
Inappropriate?
To comment on this
question,
Sign In with Facebook or
Sign Up
You might also be interested in: Interview Questions, Software Engineer Interview Questions, Google Interview
6 of 6 people found this helpful
by Interview Candidate: