what does this symbol (in c) mean? += and -=

example:
rowSum += data[row][col]

thanks

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The "+=" operator adds the value of the variable on the right to the current value of the variable on the left. The "-=" operator does the same thing, just with subtraction instead of addition.

In the example, if rowSum = 10 and data[row][col] = 14, the command "rowSum += data[row][col]" would make rowSum = 24. Get it?

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+= and -= are called short hand assignment operators.we can give a+=10 instead of a=a+10

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