AIPO2013 q2 bad solution

q2.c

#include <stdio.h>
#include <math.h>
#include <stdbool.h>

bool appToParis(unsigned self[3][2], unsigned len, unsigned val1, unsigned val2){
	unsigned i = 0;
	for(i = 0; i<len; ++i){
		if((self[i][0] == val1 && self[i][1] == val2) || (self[i][0] == val2 && self[i][1] == val1)){
			return false;
		}
	}
	self[len][0] = val1;
	self[len][1] = val2;
	return true;
}

int main(void){
	unsigned num; //to be found
	unsigned found = 0; //found already
	unsigned total; //resukls to check
	unsigned first; //x
	float tmp; //sqrt res
	unsigned last = 0; //last num
	unsigned lastn = 0; //number itself
	
	
	unsigned pairs[3][2];
	unsigned pairl = 0;
	
	scanf("%u",&num);
	
	for(total = 3; found < num; ++total){
		for(first = 3; first < total; ++first){
				tmp = sqrt(total*total - first*first);
				if((int)tmp == tmp){
					if(lastn == total){
						pairl += appToParis(pairs, pairl, first, (unsigned)tmp);
						if(pairl > 1){
							//printf("\t%u. (%u, %f, %u)\n",found, first,tmp,total);
							///printf("%u^2 + %f^2 = %u^2\n",first,tmp,total);
							printf("%u\n",total);
							break;
						}
					}else{
						++found;
						lastn = total;
						pairl = 0;
						last = 0;
					}
					//printf("\t%u. (%u, %f, %u)\n",found, first,tmp,total);
				}
		}
	}
	return 0;
}