Sum of a number's components in C

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#include<stdio.h> main() { int i,sum,sum1=0,sum2=0, sum3=0, sum4=0; { scanf("%d",&i); sum1=i%10; i=i/10; sum2=i%10; i=i/10; sum3=i%10; i=i/10; sum4=i%10; i=i/10; } sum= sum1+sum2+sum3+sum4; printf("%d\n",sum); }