Exponentiation of natural numbers using only primitive integer operations
Java, 84
A boring &quot;addition in a double loop&quot; method. One loop is to multiply, the other makes it happen more than once. Works until overflow on int types. The -10 bonus just isn't worth it in Java ;)
int p(int x,int y){int r=1,p,i=0,j;for(;i++&lt;y;r=p)for(p=0,j=0;j++&lt;x;)p+=r;return r;}