Find length of string using pointer Dry Run in C

Find length of string using pointer is an interactive C dry run visualizer from the Pointersarrays programs section. Study the source code, then use the execution controls to follow each step, variable update, highlighted line, and console output.

This page provides a browser-based dry run with source-code highlighting, auto-scroll, voice narration controls, and execution output for learning the program step by step.

Find length of string using pointer Program Code

#include <stdio.h>
#include <string.h>
int stringLength(char *str) {
    int length = 0;
    while(*str != '\0') {
        length++;
        str++;
    }
    return length;
}

int stringLengthPtr(char *str) {
    char *start = str;
    while(*str != '\0') {
        str++;
    }
    return str - start;  // Pointer difference gives length
}

int main() {
    char str[] = "Programming in C";
    
    printf("String: \"%s\"\n", str);
    printf("Length (method 1): %d\n", stringLength(str));
    printf("Length (method 2): %d\n", stringLengthPtr(str));
    
    // Using library function
    printf("Length (strlen): %lu\n", strlen(str));
    
    return 0;
}

View the complete Pointersarrays programs page.