#include<stdio.h> int main() { char c[] = "Ab1xyz874[429]2323"; int i = 0, sum = 0, j = 0, flag = 0; int a[100]={ 0 }; while (c[i] != '\0') { if (c[i] <= '9'&&c[i] >= '0') { a[flag++] = c[i] - 48; } i++; }

for (int i = 1; i < flag; i++) {
	if (a[i] == a[i - 1] + 1) {
		sum = sum * 10 + a[i-1 ];
		j++;
	}
	else if (j > 0) {
		sum = sum * 10 + a[i-1];
		break;
	}
	else {
		sum = 0;
		j = 0;
	}
}
printf("%d", sum);

}