Subarray with a given sum

Given an array, how will find a subarray with a required sum.

Answer:

Solution 1:
Recursively computing the array sum is one of the options, but no optimal.
The trick is to build the array iteratively from the previous results,
for ex: A[0..4]= a[0..3] + A[4]
Complexity : O(m*n/2)

#include 
#include 
#include 
#include 
using namespace std;

int main(int argc, char *argv[])
{
    if (argc <= 1)
        return -1;

    vector a(argc);
    int s[10][10]={};
    const int n = argc-1;

    for(int i = 1; i< argc; ++i)
        a[i] = atoi(argv[i]);

    copy(a.begin(), a.end(), ostream_iterator(cout, " "));
    cout << endl << "----" << endl;

    for(int i = 1; i<= n; ++i)
        s[i][i] = a[i];

    for ( int i = 1; i <= n; ++i )
    {
        for (int j = i+1; j <=n; ++j)
        {
            s[i][j] = s[i][j-1] + a[j];
            printf("[%d][%d] = %d ", i, j, s[i][j]);
            /* if s[i][j] is the required result print it, 
             * and the sub array is [i,j]
             * */
        }
        printf("\n");
    }
    return 0;
}