69 lines
1.8 KiB
C
69 lines
1.8 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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int main(int argc, const char *argv[])
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{
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int value = 42;
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if (value >= 27)
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{
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// This part of the program is only executed, if the expression is true
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printf("value is indeed bigger or equal to 27 \n");
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}
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// the else-statement will be executed if the if-statement wasn't true
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if (value == 43)
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{
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// This will not be executed
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printf("value is equal 43 \n");
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}
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else
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{
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// This part will be executed
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printf("value is not equal to 43 \n");
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}
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// Another useful syntax is else if statement.
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// You want to use it if you want to test for multiple things.
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// But be careful! The first condition, which is true, gets executed.
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if(value != 42)
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{
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// This will not be executed
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printf("value is not equal to 42 \n");
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}
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else if(value < 45)
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{
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// This will be executed
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printf("value is less than 45 \n");
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}
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else if( value == 42)
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{
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// This will not be executed
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printf("value is equal to 42\n");
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}
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// You can also chain expressions together with the logical operators like && for and || for or and ! for not
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if(!(value >= 0 && value <42))
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{
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printf("Value is not bigger or equal to 0 and less than 42\n");
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}
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// in c any value other then 0 is considered to be true
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// even negative values are true
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if(value)
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{
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// this is legal in c and will be considered as true
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}
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// this is a great way to check for null-pointers
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int Value1 = atoi(argv[1]);
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int Value2 = atoi(argv[2]);
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// We prepared the variables Value1 and Value2 to hold values,
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// which are passed to the program
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// TODO: compare these to values the following way
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// if value1 is bigger write to the standart output "value 1 is bigger"
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// if value2 is bigger write to the standart output "value 2 is bigger"
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// otherwise print out "value 1 is equal to value 2"
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}
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