Author: program45_-rt8nb

Fibonacci series means a series of numbers in which each number is the sum of the two preceding numbers. Example is 1, 1, 2, 3, 5, 8

Below is C program code to print Fibonacci series as per user input.

for e.g if user input 20 then program will print 20 elements in Fibonacci series.

//Program Name: Print fibonacci series using for loop upto n term
// for e.g 1, 1, 2, 3, 5, 8

#include <stdio.h>

void main()
{
    int s1=0,s2=1; //initializing first two numbers 
    int nextNum=0,numCnt=0,i;

    printf("\n\n\tPlease enter how many numbers need to print in Fibonacci series.\t");
    scanf("%d",&numCnt);
    //here assuming user will enter value more than 1 
    //printing first two numbers
    printf("\n\tBelow are %d numbers in Fibonacci Series  ",numCnt);
    printf("\n\n\t%d %d",s1,s2);
     for(i=2;i<numCnt;i++)
    {    
        nextNum=s1+s2;
        printf(" %d",nextNum); 
        s1=s2;    
        s2=nextNum; 
       
    }  
}

Output

        Please enter how many numbers need to print in Fibonacci series.       20

        Below are 20 numbers in Fibonacci Series  

        0 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987 1597 2584 4181

If you want to print Fibonacci series up to particular number then refer this link

Fibonacci series means a series of numbers in which each number is the sum of the two preceding numbers. Example is 1, 1, 2, 3, 5, 8

Below is C program code to print Fibonacci series as per user input or up to n number.

for e.g if user input 200 then program will print Fibonacci series till 200 meaning sum which is less than or equal to 200.

//Program Name: Print fibonacci series using for loop upto n term
// for e.g 1, 1, 2, 3, 5, 8

#include <stdio.h>

void main()
{
    int s1=0,s2=1; //initializing first two numbers 
    int nextNum=0,SumUpto=0;

    printf("\n\n\tPlease enter number up to which print Fibonacci series is required \t");
    scanf("%d",&SumUpto);
    //here assuming user will enter value more than 1 
    //printing first two numbers
    printf("\n\tfibbonacci Series up to %d is ",SumUpto);
    printf("\n\n\t%d  %d",s1,s2);
     for(nextNum=2;nextNum<=SumUpto;)
    {    
 
        s1=s2;    
        s2=nextNum; 
        printf(" %d",nextNum); 
        nextNum=s1+s2;
    }  
}

Output

        Please enter number up to which print Fibonacci series is required      200

        Fibonacci Series up to 200 is 

        0  1 2 3 5 8 13 21 34 55 89 144

Another method to find the Fibonacci numbers is by using the golden ratio (1.618034).

Here is a method to find the Fibonacci series using the golden ratio method.

Just by multiplying the previous Fibonacci Number by the golden ratio(1.618034), we get the approximated Fibonacci number. For example, 2 × 1.618034… = 3.236068. This gives the next Fibonacci number 2 after 3.

C code for Fibonacci series using the golden ratio.

// Fibbonaci series using golden ratio.
#include <stdio.h>
#include <math.h>
int main() {
    // Write C code here
    float result=1.0;
    //result=1.0;
    printf("\n0\n1\n1");
    for(int i=1;i<15;i++)
    {
        result = lround( result * (1.618034));
        printf("\n%d",lround(result));
    }
}

Output

0
1
1
2
3
5
8
13
21
34
55
89
144
233
377
610
987

Below running code will accept 3 Numbers from user.

Based on results given in expression in ternary operator program will return smallest number

// Program Name: C Program to find smallest number using Ternary operator
#include <stdio.h>

void main()
{
    int num1,num2,num3;
    int counter;
    printf("\n\tEnter first Integer Number\t");
    scanf("%d",&num1);
    printf("\n\tEnter Second Integer Number\t");
    scanf("%d",&num2);
    printf("\n\tEnter Third Integer Number\t");
    scanf("%d",&num3);
    
    
    // Ternary operator
    counter = (num1 < num2) ? (num1 < num3 ? num1:num3) : (num2 < num3 ? num2:num3);
    
    printf("\n\t Minimum of 3 Number is %d", counter);
}

Output

        Enter first Integer Number      11

        Enter Second Integer Number     90

        Enter Third Integer Number      32

         Minimum of 3 Number is 11

To find another method Click here . Program to find smallest number without comparison

Program to find largest or greatest of 3 number using ternary operator

Accept 3 numbers from user using scanf. User ternary operator to compare them and print result using printf. Here is complete code.

// Program Name: C Program to find largest number using Ternary operator
#include <stdio.h>

void main()
{
    int num1,num2,num3;
    int counter;
    printf("\n\tEnter first Integer Number\t");
    scanf("%d",&num1);
    printf("\n\tEnter Second Integer Number\t");
    scanf("%d",&num2);
    printf("\n\tEnter Third Integer Number\t");
    scanf("%d",&num3);
    
    
    // Ternary operator
    counter = (num1 > num2) ? (num1 > num3 ? num1:num3) : (num2 > num3 ? num2:num3);
    
    printf("\n\t Largest of 3 Number is %d", counter);
}

Output

Enter first Integer Number	4
Enter Second Integer Number	5
Enter Third Integer Number	6
Largest of 3 Number is 6

There are many ways to find smallest. Below program will accept 3 integer numbers from user

We are using while loop here and one increment variable.

Every time program is subtracting value by 1 and incrementing counter variable by 1. once condition is false program will return smallest number. This is simple basic mathematical operation. Below is complete running code.

// Program Name: C Program to find smallest number without comparison
#include <stdio.h>

void main()
{
    int num1,num2,num3;
    int counter=0;
    printf("\n\tEnter first Integer Number\t");
    scanf("%d",&num1);
    printf("\n\tEnter Second Integer Number\t");
    scanf("%d",&num2);
    printf("\n\tEnter Third Integer Number\t");
    scanf("%d",&num3);
    
    
    // Here we are using while loop when result is false we will get smallest number 
    while(num1 && num2 && num3)
    {
        num1--;
        num2--;
        num3--;
        counter++;
    }
    printf("\n\t Minimum of 3 Number is %d", counter);
}

Output

Enter first Integer Number      4

        Enter Second Integer Number     3

        Enter Third Integer Number      0

         Minimum of 3 Number is 0