#include <stdio.h>
#include <stdint.h>
#include <string.h>
#define MAX 10
void process_stack(int n) {
int stack[MAX];
int top = -1;
char line[100];
for(int i = 0; i < n; i++){
fgets(line, sizeof(line), stdin);
if(strncmp(line, "push", 4) == 0){
int x;
sscanf(line + 5,"%d", &x);
if(top == MAX - 1) printf("Stack Overflow\n");
else stack[++top] = x;
}
else if(strncmp(line, "pop", 3) == 0){
if(top == -1) printf("Stack Underflow\n");
else printf("%d\n", stack[top--]);
}
}
}
int main() {
int n;
scanf("%d", &n);
getchar(); // Consume newline after number
process_stack(n);
return 0;
}
Input
5 push 10 push 20 pop pop pop
Expected Output
20 10 Stack Underflow