do

do is similar to while except that the continuation condition is tested at the end of the loop rather than at the beginning; it follows that the body of the loop is certain to be executed at least once:

int a[10]; int i; /* .. */ i=0; do { /* write out the initial increasing segment of a */ printf("%d", a[i]); i = i+1; } while (i<9 && a[i] >= a[i-1])