What do the n and m stand for in the PayPal API variables like L_PAYMENTREQUEST_n_NAMEm

Try as I might, I can't seem to find what the n and m stand f开发者_JAVA技巧or in the api variable request format above. I'm guessing m stands for different items, but not sure what n stands for.

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'n' is the number of your payment request. If you have one payment request going on at a time, this will be 0. If you have multiple (if you want to use parallel payments, for example), it would be 0 for the first payment request, 1 for the second, et cetera.

'm' is the specific product within that payment request.

E.g.

// First payment request
PAYMENTREQUEST_0_SELLERPAYPALACCOUNTID=test@example.com
PAYMENTREQUEST_0_AMT=10
L_PAYMENTREQUEST_0_NAME0=Test+product

// Second payment request
PAYMENTREQUEST_1_SELLERPAYPALACCOUNTID=test@anotherexample.com // Recipient of this payment request
PAYMENTREQUEST_1_AMT=5 // Total of all products combined in this payment request
L_PAYMENTREQUEST_1_NAME0=Test+product+2 // Name of the first product/item in this payment request
L_PAYMENTREQUEST_1_AMT0=2.50 // Price of this one product
L_PAYMENTREQUEST_1_NAME1=Test+product+3 // Name of the second product/item in this payment request
L_PAYMENTREQUEST_1_AMT1=2.50 // Price of this one product

Source: https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/e_howto_api_ECParallelPaymens