Print all pairs of numbers from an array that adds up to M. Assume input is sorted.

PrintAllPairsAdduptoM.java

public static void PrintAllPairs(int[] sorted, int M)
  {
	  	//as the key is to keep track of two indexes, left and right, we define the indexes
	  	int left = 0;//leftmost
	  	int right = sorted.length-1;//rightmost
				//now we start our loop, and only make sure left not meet right will we proceed
	    	while(left<right)
	    	{
		    	int tempSum = sorted[left] + sorted[right];//calculate the temp sum and use it to compare to M
		    	if(tempSum==M)//great we find one pair!
		    	{
			    	//format the output per line as "Sum{1,10}=11"
			    	System.out.println("Sum of {"+sorted[left]+", "+sorted[right]+"} = "+M);
			    	//do not forget the update both index values
			    	left++;
			    	right--;
		    	}
		    	else if(tempSum>M)//as the temp sum is bigger than M, 
								    //we need more right focus left to make the future sum smaller
		    		right--;
		      	else//the only remaining case is temp sum smaller than M, so move left focus right 
			    	left++;
	    	}

}