How '0' becomes a false value in PHP

<?php
if('0')
{
    echo 1;
}
else
{
    echo 0;
}
// outputs 0, because 'if' statement needs to convert '0' into boolean type value to work and in PHP (bool)'0' creates boolean false


if('0' == false) // because of loose comparison '0' will be converted into boolean type automatically
{
    echo 1;
}
else
{
    echo 0;
}
//ouputs 1

if('0' === false)
{
    echo 1;
}
else
{
    echo 0;
}
// outputs 0, because '0' is a string after all and false is boolean, so their type didn't match here and for strict comparison no type conversion happened
?>

Comments

Post a Comment

Popular posts from this blog

Timus 1209. 1, 10, 100, 1000... accepted solution in C

#include <stdio.h> int binary_search(int ara[], int n, int ara_size) {     int min, max, mid;     min = 0;     max = ara_size - 1;     while(min <= max)     {         mid = min + (max - min) / 2;         if(ara[mid] == n) {             return 1;         } else if(ara[mid] < n) {             min = mid + 1;         } else {             max = mid - 1;         }     }     return 0; } int main() {     int N, K, i;     int ones_indexes[65536]; // there will be total 65536 ones in the 110100100010001... sequence fo...
Read more

Timus Problem 1086. Cryptography Accepted Solution in C

#include <stdio.h> #include <math.h> #include <stdlib.h> int main() {     int i, j, k, n, count, square_root, current_number;     char is_prime[163842];     int prime_numbers[15001];     square_root = (int)sqrt(163841); // 163841 is the 1500th prime number     for(i = 2; i <= 163841; i++) is_prime[i] = '1';     for(i = 2; i <= square_root; i++)     {         if(is_prime[i] == '1')         {             current_number = i * i;             while(current_number <= 163841)             {                 is_prime[current_number] = '0'; ...
Read more

Timus 1083. Factorials!!! Accepted Solution in C

#include <stdio.h> int main() {     int i, n, k, sum;     char input[24];     gets(input);     if(input[1] == ' ') {         n = input[0] - '0';         i = 2;     } else {         n = 10;         i = 3;     }     k = i;        while(input[i]) i++;     k = i - k;     sum = 1;     for(i = n; i > 0; i -= k) sum *= i;     printf("%d", sum);     return 0; }
Read more