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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include <QtCore>
void slowOperation1()
{
static char buf[256];
for (int i = 0; i < (1<<20); ++i)
buf[i % sizeof buf] = i;
}
void slowOperation2(int) { slowOperation1(); }
void startExample()
{
//![0]
QElapsedTimer timer;
timer.start();
slowOperation1();
qDebug() << "The slow operation took" << timer.elapsed() << "milliseconds";
//![0]
}
//![1]
void executeSlowOperations(int timeout)
{
QElapsedTimer timer;
timer.start();
slowOperation1();
int remainingTime = timeout - timer.elapsed();
if (remainingTime > 0)
slowOperation2(remainingTime);
}
//![1]
//![2]
void executeOperationsForTime(int ms)
{
QElapsedTimer timer;
timer.start();
while (!timer.hasExpired(ms))
slowOperation1();
}
//![2]
int restartExample()
{
//![3]
QElapsedTimer timer;
int count = 1;
timer.start();
do {
count *= 2;
slowOperation2(count);
} while (timer.restart() < 250);
return count;
//![3]
}
int main(int argc, char **argv)
{
QCoreApplication app(argc, argv);
startExample();
restartExample();
executeSlowOperations(5);
executeOperationsForTime(5);
}