## INDEX

### c programming questions and answers

31. SUM OF SQUARES OF THE SERIES 12+22+32+--------+n2
void main()
{
long int r;
clrscr();
printf("\nEnter the range: ");
scanf("%ld",&r);
printf("\nSum of the squares of the series is: %ld",((r*(r+1))*(2*r+1))/6);
getch();
}
32. SUM OF CUBES OF THE SERIES 13+23+33+---------+n3
void main()
{
int r;
clrscr();
printf("\nEnter the number range: ");
scanf("%d",&r);
printf("\nSum of the cubes of the series is: %d",(r*(r+1)/2)*(r*(r+1)/2));
getch();
}
33. LARGEST NUMBER IN AN ARRAY
void main()
{
int a[50],size,i,big;
clrscr();
printf("\nEnter the size of the array: ");
scanf("%d",&size);
printf("\nEnter %d elements in to the array: ”, size);
for(i=0;i<size;i++)
scanf("%d",&a[i]);
big=a[0];
for(i=1;i<size;i++)
{
if(big<a[i])
big=a[i];
}
printf("\nBiggest: %d",big);
getch();
}
34. SECOND LARGEST NUMBER IN AN UNSORTED ARRAY
main()
{
int un[10], i, big1, big2;
printf("Enter array elements: ");
for ( i = 0; i < 10; ++i )
scanf("%d", &un[i]);
big1 = un[0];
for ( i = 1; i < 10; ++i )
{
if ( big1 < un[i] )
big1 = un[i];
if ( big1 != un[0] )
big2 = un[0];
else
big2 = un[1];
}
for ( i = 1; i < 10; ++i )
{
if ( big1 != un[i] && big2 < un[i] )
big2 = un[i];
}
printf("Second largest: %d\n", big2);
return 0;
}
35. SECOND SMALLEST NUMBER IN AN UNSORTED ARRAY
main()
{
int un[10], i, s1, s2;
clrscr();
printf("Enter array elements: ");
for ( i = 0; i < 10; ++i )
scanf("%d", &un[i]);
s1 = un[0];
for ( i = 1; i < 10; ++i )
{
if ( s1 > un[i] )
s1 = un[i];
if ( s1 != un[0] )
s2 = un[0];
else
s2 = un[1];
}
for ( i = 1; i < 10; ++i )
{
if ( s1 != un[i] && s2 > un[i] )
s2 = un[i];
}
printf("\nSecond smallest: %d", s2);
return 0;
}
36. MULTIPLICATION OF MATRICES
void main()
{
int a[5][5],b[5][5],c[5][5],i,j,k,sum=0,m,n,o,p;
clrscr();
printf("\nEnter the row and column of first matrix");
scanf("%d %d",&m,&n);
printf("\nEnter the row and column of second matrix");
scanf("%d %d",&o,&p);
if(n!=o)
{
printf("Matrix mutiplication is not possible");
printf("\nColumn of first matrix must be same as row of second matrix");
}
else
{
printf("\nEnter the First matrix->");
for(i=0;i<m;i++)
for(j=0;j<n;j++)
scanf("%d",&a[i][j]);
printf("\nEnter the Second matrix->");
for(i=0;i<o;i++)
for(j=0;j<p;j++)
scanf("%d",&b[i][j]);
printf("\nThe First matrix is\n");
for(i=0;i<m;i++)
{
printf("\n");
for(j=0;j<n;j++)
{
printf("%d\t",a[i][j]);
}
}
printf("\nThe Second matrix is\n");
for(i=0;i<o;i++)
{
printf("\n");
for(j=0;j<p;j++)
{
printf("%d\t",b[i][j]);
}          }
for(i=0;i<m;i++)
for(j=0;j<p;j++)
c[i][j]=0;
for(i=0;i<m;i++)//row of first matrix
{
for(j=0;j<p;j++)//column of second matrix
{
sum=0;
for(k=0;k<n;k++)
sum=sum+a[i][k]*b[k][j];
c[i][j]=sum;
}
}
}
printf("\nThe multiplication of two matrix is\n");
for(i=0;i<m;i++)
{
printf("\n");
for(j=0;j<p;j++)
{
printf("%d\t",c[i][j]);
}
}
getch();
}
37. SUM OF DIAGONAL ELEMENTS OF A MATRIX
void main()
{
int a[10][10],i,j,sum=0,m,n;
clrscr();
printf("\nEnter the row and column of matrix");
scanf("%d %d",&m,&n);
printf("\nEnter the First matrix->");
for(i=0;i<m;i++)
for(j=0;j<n;j++)
scanf("%d",&a[i][j]);
printf("\nThe matrix is\n");
for(i=0;i<m;i++)
{
printf("\n");
for(j=0;j<m;j++)
{
printf("%d\t",a[i][j]);
}
}
for(i=0;i<m;i++)
{
for(j=0;j<n;j++)
{
if(i==j)
sum=sum+a[i][j];
}
}
printf("\n\nSum of the diagonal elements of a matrix is -> ");
printf("%d",sum);
getch();
}
38. TRASPOSE OF A MATRIX
void main()
{
int a[10][10],b[10][10],i,j,k=0,m,n;
clrscr();
printf("\nEnter the row and column of matrix");
scanf("%d %d",&m,&n);
printf("\nEnter the First matrix->");
for(i=0;i<m;i++)
for(j=0;j<n;j++)
scanf("%d",&a[i][j]);
printf("\nThe matrix is\n");
for(i=0;i<m;i++)
{
printf("\n");
for(j=0;j<m;j++)
{
printf("%d\t",a[i][j]);
}
}
for(i=0;i<m;i++)
for(j=0;j<n;j++)
b[i][j]=0;
for(i=0;i<m;i++)
{
for(j=0;j<n;j++)
{
b[i][j]=a[j][i];
printf("\n%d",b[i][j]);
}
}
printf("\n\nTraspose of a matrix is -> ");
for(i=0;i<m;i++)
{
printf("\n");
for(j=0;j<m;j++)
{
printf("%d\t",b[i][j]);
}
}
getch();
}
39. CONVERSION OF FAREHNITE TO CENTIGRADE
void main()
{
float c,f;
clrscr();
printf("Enter temp. in farehnite");
scanf("%f",&f);
c=(5*(f-32))/9;//Formula for conversion
printf("The temp. in centigrade is->%f",c);
getch();
}
40. COUNTING DIFFERENT CHARACTERS IN A STRING
main()
{
int a[26],A[26],i,c=0;
char str[100];
clrscr();
puts("Enter a string->");
gets(str);
for(i=0;i<26;i++)
{
a[i]=0;
A[i]=0;
}
for(i=0;str[i]!='\0';i++)
{
c=str[i];
if(c<97)
{
c=c-65;
A[c]++;
}
else
{
c=c-97;
a[c]++;
}
}
for(i=0;i<26;i++)
{
if(a[i]!=0)
printf("\n%c occurs %d times",i+97,a[i]);
}
for(i=0;i<26;i++)
{
if(A[i]!=0)
printf("\n%c occurs %d times",i+97,A[i]);
}
getch();
}
41. SORTING OF STRING
void main()
{
int i,j,n;
char str[20][20],temp[20];
clrscr();
puts("Enter the no. of string to be sorted");
scanf("%d",&n);
for(i=0;i<=n;i++)
gets(str[i]);
for(i=0;i<=n;i++)
for(j=i+1;j<=n;j++)
{
if(strcmp(str[i],str[j])>0)
{
strcpy(temp,str[i]);
strcpy(str[i],str[j]);
strcpy(str[j],temp);
}
}
printf("The sorted string\n");
for(i=0;i<=n;i++)
puts(str[i]);
getch();
}
42. BUBBLE SORT
void main()
{
int s,temp,i,j,a[20];
clrscr();
printf("\nEnter size of the array: ");
scanf("%d",&s);
printf("\nEnter %d elements in to the array:",s);
for(i=0;i<s;i++)
scanf("%d",&a[i]);
for(i=0;i<s-1;i++)
{
for(j=0;j<s-1-i;j++)
{
if(a[j]>a[j+1])
{
temp=a[j];
a[j]=a[j+1];
a[j+1]=temp;
}
}
}
printf("\nThe array after sorting is: ");
for(i=0;i<s;i++)
printf(" %d",a[i]);
getch();
}
43. SELECTION SORT
void main()
{
int s,i,j,temp,a[20];
clrscr();
printf("\nEnter size of the array :");
scanf("%d",&s);
printf("\nEnter %d elements in to the array:");
for(i=0;i<s;i++)
scanf("%d",&a[i]);
for(i=0;i<s;i++)
{
for(j=i+1;j<s;j++)
{
if(a[i]>a[j])
{
temp=a[i];
a[i]=a[j];
a[j]=temp;
}
}
}
printf("\nThe array after sorting is: ");
for(i=0;i<s;i++)
printf(" %d",a[i]);
getch();
}
44. INSERTION SORT
void main()
{
int i,j,s,temp,a[20];
clrscr();
printf("\nEnter size of the array: ");
scanf("%d",&s);
printf("\nEnter %d elements in to the array:",s);
for(i=0;i<s;i++)
scanf("%d",&a[i]);
for(i=1;i<s;i++)
{
temp=a[i];
j=i-1;
while((temp<a[j])&&(j>=0))
{
a[j+1]=a[j];
j=j-1;
}
a[j+1]=temp;
}
printf("\nAfter sorting the elements are: ");
for(i=0;i<s;i++)
printf(" %d",a[i]);
getch();
}
45. DISPLAY SOURCE CODE AS OUTPUT
#include"stdio.h"
void main()
{
FILE *p;
char ch;
clrscr();
p=fopen("raja.c","r");
while((ch=getc(p))!=-1)
putchar(ch);
fclose(p);
getch();
}
46. FACTORIAL OF A NUMBER USING RECURSION
void main()
{
int num,f;
clrscr();
printf("\nEnter a number: ");
scanf("%d",&num);
f=fact(num);
printf("\nFactorial of %d is: %d",num,f);
getch();
}
int fact(int n)
{
if(n==1)
return 1;
else
return(n*fact(n-1));
}
47. GCD OF A NUMBER USING RECURSION
void main()
{
int n1,n2,gcd;
clrscr();
printf("\nEnter two numbers: ");
scanf("%d %d",&n1,&n2);
gcd=findgcd(n1,n2);
printf("\nGCD of %d and %d is: %d",n1,n2,gcd);
getch();
}
int findgcd(int x,int y)
{
while(x!=y)
{
if(x>y)
return findgcd(x-y,y);
else
return findgcd(x,y-x);
}
return x;
}
48. SUM OF DIGITS OF A NUMBER USING RECURSION
void main()
{
int num,x;
clrscr();
printf("\nEnter a number: ");
scanf("%d",&num);
x=findsum(num);
printf("Sum of the digits of %d is: %d",num,x);
getch();
}
int r,s;
int findsum(int n)
{
if(n)
{
r=n%10;
s=s+r;
findsum(n/10);
}
else
return s;
}
49. POWER OF A NUMBER
void main()
{
int pow,num,i=1;
long int sum=1;
clrscr();
printf("\nEnter a number: ");
scanf("%d",&num);
printf("\nEnter power: ");
scanf("%d",&pow);
while(i<=pow)
{
sum=sum*num;
i++;
}
printf("\n%d to the power %d is: %ld",num,pow,sum);
getch();
}
50. POWER OF A NUMBER USING RECURSION
void main()
{
int pow,num;
long int res;
long int power(int,int);
clrscr();
printf("\nEnter a number: ");
scanf("%d",&num);
printf("\nEnter power: ");
scanf("%d",&pow);
res=power(num,pow);
printf("\n%d to the power %d is: %ld",num,pow,res);
getch();
}
int i=1;
long int sum=1;
long int power(int num,int pow)
{
if(i<=pow)
{
sum=sum*num;
power(num,pow-1);
}
else
return sum;
}