Program to Perform Arithmetic Operations Without Using Arithmetic Operators in C

Question

It is one of most frequently asked interview question to perform any arithmetic operations(add,subtract,multiply,divide) without using arithmetic operators.

Logic

• The logic is simple. We have to use loop and manipulate the value of  one variable with value of another variable. This will help us calculate the addition and subtraction.
• Nested loops can help us to perform Division and multiplication. We perform same addition/ subtraction operation more number of times to get the result.

Program:

#include <stdio.h>
 //Compiler version gcc 6.3.0
 //Program to perform arithmetic operations
 //Without  arithmetic operator

 int main()
 {
 	int a,b,c,i=0,j=0,t=0,temp; //intialization for using in below programs
 	int n; // initialize for switch
 	printf("Enter First Value\n");
	scanf("%d",&a); // read value 1
	printf("Enter Second Value\n");
	scanf("%d",&b);// read value 2
	printf("Choose Operation:\n");
	printf("1.ADD\n2.SUBTRACT\n3.MULTIPLE\n4.DIVIDE\n");
	scanf("%d",&n);// read integer for switch case
	/*
	Before move to perform operation, we should change
	the big value to variable a and small value to variable b.
	Its minimize the execution time.
	*/
	//Swapping function
	if(a<b)
 	{
 		t=b;
 		b=a;
 		a=t;
 	}
 		switch(n)
 		{
 			case 1: //for addition operation
 			while(b>i) // check b(low value)  with i
           {

 		    a++; //increment once
 		    i++; //increment i
 	       } // the loop execute until the b equals to i and a was incremented.
 	       //now the value of a is equal to a+b
 	        printf("%d",a);
 	        break;
 	        case 2://for subtraction operation
 	        while(b>i) // check b(low value)  with i
 	        {
         		a--;//decrement once
         		i++; //increment i
         	}// the loop execute until the b equals to i and a was incremented.
 	       //now the value of a is equal to a-b
         	printf("%d",a);
         	break;
         	case 3://for multiplication operation
         	temp=a; //in that time we use same addition loop with a times.so we use nested loop.
         	i=1;
         	while(b>i)
         	{
         		while(temp>j)
         		{
         			a++;
         			j++;
         		}
         		j=0;
         	i++;
         	}
         	printf("%d",a);
         	break;
         	case 4: //for division operation
         	i=0;c=0;
         	t=b; //in that time we use same subtraction loop with a times.so we use nested loop.
         	while(a>t)
			{
			while(b>i)
 	        {
         		a--;
         		i++;
         	}
         	i=0;
			c++; //we count the number of times subtracted
			}
         	printf("%d",c+1); //print the last count of subtraction value
         	break;
         	break;
 		}
 	return 0;
 }

Keywords:

Program to Perform Arithmetic Operations without Arithmetic Operator

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Program to Perform Subtraction Operation without Arithmetic Operators

Program to Perform Multiplication Operation without Arithmetic Operators

Program to Perform Division Operation without Arithmetic Operators