56 lines
859 B
Markdown
56 lines
859 B
Markdown
---
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title: While-loop
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---
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A while loop statement repeatedly executes a target statement as long as a given condition is true.
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Syntax:
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```C++
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while(condition) {
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statement(s);
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}
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```
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A key point of the while loop is that the loop might not ever run.
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When the condition is tested and the result is false, the loop body will be skipped and the first statement after the while loop will be executed.
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Example:
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```C++
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#include <iostream>
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using namespace std;
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int main () {
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// Local variable declaration:
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int a = 10;
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// while loop execution
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while( a < 20 ) {
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cout << "value of a: " << a << endl;
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a++;
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}
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return 0;
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}
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```
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Output:
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```
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value of a: 10
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value of a: 11
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value of a: 12
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value of a: 13
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value of a: 14
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value of a: 15
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value of a: 16
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value of a: 17
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value of a: 18
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value of a: 19
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```
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### Sources
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- www.tutorialspoint.com
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