. .
: for, while, do... while.
. , , , .
for , while do... while , : while , do... while .
for while ( ) , , , . do... while do while, , .
. for : ( ), , ( ). for .
for , , .. , S 0, . 1 n.
S= = 12 + 2 2 +... + n 2.
:
//sum_sq.c
#include<stdio.h>
#include<conio.h>
main()
{ int S,n,i;
clrscr();
printf( n\n);
scanf(%d,&n);
for(S=0,i=1;i<=n;i++) S+=i*i;
printf(n=%d S=%d\n,n,S);
getch();
return 0; }
S, n, i. () . clrscr, , conio.h. n for. S ( ) i , , . i n, i n , . ( 1) i. i++ i=i+1.
S+=i*i; , S=S+i*i, . ( printf). getch, conio.h, , , [ALT]+[F5].
, , F, , 0, 1.