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ctypesprintfspecifier

Multiplying numbers in C

I have written the following code to multiply two numbers and I see the result to be incorrect. I assume the data type is not holding the value right. But the answer its printing is incorrect.

#include<stdio.h>
main()
{
    long int val1,val2;
    val1=val2=1235;
    char c = 'y';
    switch(c)
    {
        case 'y' : printf("%20d",val1*val2);
            break;
        default: printf("invalid");
            break;
    }
    return 0;
}

OUTPUT :
17897 //which is not the right answer
//it should actually be 1525225

Solution

  • Data type is holding the right value but you are using the wrong specifier. You should use %ld with long int.

    printf("%20ld",val1*val2);

    I double checked and it worked.