for( expr1; test; expr2 ) expr3;
The for statement. Expression test must be a boolean expression. No comma operator is permitted like in C/C++ for expressions expr1 nor expr2. Expression expr3 stands for a single statement or a block of statements.
Example
printf( " i i*i\n" );
for( i=1; i<=n; i++ ) {
j = i*i;
printf( "%10d%20d\n", i, j );
}