Program to check whether given number is a perfect number or not
A number is a perfect number if it is equal to sum of all of it's positive divisors excluding itself
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/*Programme to check whether a given number is a perfect number or not*/ 
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#include <stdio.h> 
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#include <conio.h> 
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void main() 
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{ 
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int num,i,sum=0; 
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printf("Enter a Number to chech it's perfection and 0 to quit: "); 
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scanf("%d",&num); 
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/*If vlaue entered by user is greater than 0 then continue else exit*/ 
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while(num!=0) 
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{ 
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/*Calculate the sum of all the positive divisors*/ 
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for(i=1; i<num; i++) 
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{ 
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if(num%i==0) 
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{ 
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printf("%d + ",i); 
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sum=sum+i; 
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} 
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} 
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/*Check if the sum=num*/ 
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if(num==sum) 
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{ 
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printf("= %d",sum); 
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printf("Perfet Number"); 
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} 
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else 
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{ 
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printf("= %d",sum); 
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printf("Not a perfet Number"); 
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} 
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sum=0; 
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printf("Enter a Number to chech it's perfection and 0 to quit: "); 
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scanf("%d",&num); 
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} 
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} 
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