C编程基础-基础篇 1

//单行注释

/*多行注释*/

#define PI 3.14159

const float PI = 3.14159;

#include <stdio.h>

int main() {
    int count, i;
    count = scanf("%d", &i);
    printf("you input %d number, the number is %d\n", count, i);

    return 0;
}

1
you input 1 number, the number is 1

#include <stdio.h>

int main() {
    char str[20];
    fgets(str, 20, stdin);
    printf("%s", str);

    return 0;
}

1
1

#include <stdio.h>

int main() {
    printf("welcome to our lessons!\n");

    return 0;
}

welcome to our lessons!

#include <stdio.h>

int main() {
    puts("welcome to our lessons!");

    return 0;
}

welcome to our lessons!