equalSumSwap_sorting.java

boolean isEqualSum(int[] a, int[] b) {
	Arrays.sort(a);
	Arrays.sort(b);
	
	int sumA = Arrays.stream(a).sum();
	int sumB = Arrays.stream(b).sum();

	int diff = sumB - sumA;

	if(diff % 2 == 1) {
		return false;
	} else {
		diff = diff / 2;
	}

	int j = 0;
	for(int i=0;i<a.length;i++) {
        	int currdiff = b[j] - a[i];
        	if(diff == currdiff) {
                	return true;
        	} else if(currdiff < diff) {
                	j++;
        	} else if(currdiff > diff) {
                	continue;
        	}
	}
	return false;
}