C/整数加一.c

#include <stdio.h>
#include <string.h>

#define MAX_LENGTH 52

void addone(char num[]);

int main() {
    char num[MAX_LENGTH];
    scanf("%s", num);

    addone(num);

    printf("%s\n", num);

    return 0;
}

void addone(char num[]) {
    int length = strlen(num); 
    int carry = 1;
    int i;
    for (i = length - 1; i >= 0; i--) {
        int digit = num[i] - '0' + carry;
        num[i] = (digit % 10) + '0';
        carry = digit / 10;
    }

    if (carry > 0) {
        if (length == MAX_LENGTH - 1) {
            printf("\n");
            return;
        }
        int i;
        for (i = length; i >= 0; i--) {
            num[i + 1] = num[i];
        }
        num[0] = carry + '0';
    }
}