Interview Question
Country: United States
#include<stdio.h>
int main()
{
int inp=9,inpArray[20]={3,1,4,5,2,6,9,8},missingnumber,i=0,j,temp,comparingNumber,len=0;
while(inpArray[i]!='\0')
{
len++;
i++;
}
for(i=0;i<len;i++)
{
for(j=i+1;j<len;j++)
{
if(inpArray[i]>inpArray[j])
{
temp=inpArray[i];
inpArray[i]=inpArray[j];
inpArray[j]=temp;
}
}
}
comparingNumber=inp;
for(i=len-1;i>=0;i--,comparingNumber--)
{
if(comparingNumber==inpArray[i])
{
continue;
}
else
{
missingnumber=comparingNumber;
break;
}
}
printf("%d",missingnumber);
return 0;
}
Add all array elements and subtract from n*(n+1)/2
- Satveer Singh June 05, 2014