# C Variable Values

## Change Variable Values

If you assign a new value to an existing variable, it will overwrite the previous value:

### Example

int myNum = 15;  // myNum is 15
myNum = 10;  // Now myNum is 10
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You can also assign the value of one variable to another:

### Example

int myNum = 15;

int myOtherNum = 23;

// Assign the value of myOtherNum (23) to myNum
myNum = myOtherNum;

// myNum is now 23, instead of 15
printf("%d", myNum);
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Or copy values to empty variables:

### Example

// Create a variable and assign the value 15 to it
int myNum = 15;

// Declare a variable without assigning it a value
int myOtherNum;

// Assign the value of myNum to myOtherNum
myOtherNum = myNum;

// myOtherNum now has 15 as a value
printf("%d", myOtherNum);
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## Add Variables Together

To add a variable to another variable, you can use the + operator:

### Example

int x = 5;
int y = 6;
int sum = x + y;
printf("%d", sum);
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## Exercise:

Display the sum of 5 + 10, using two variables: x and y.

= ;
int y = 10;
printf("%d", x + y);

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