Assume you have an array of numbers, where each value occurs at most twice. We consider sums of contiguous numbers in the array. But we only consider such sums whose two endpoints have the same value. The sum includes the two equal values themselves. So if the two equal numbers are at index i and index j(i < j) in array A, then we sum all the values A[i], A[i 1], . . . , A[j].

Abank manager wants to encourage new customers to open accounts with principals of at least $2 comma 500. he decides to make a poster advertising a simple interest rate of 3%. what must the principal be if the bank manager also wants to advertise that one can earn $10 the first month? can the poster correctly say, "open an account of $2 comma 500 and earn at least $10 interest in 1 month! "?