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// 7. Reverse Integer
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*
* given a signed 32-bit integer 'x', return 'x' with its digits reversed. if
* reversing 'x' causes the value to go outside the signed 32-bit integer range,
* then return 0
*/
int reverse(int x) {
int negative = 0, len, tmp;
if (x) {
if (x < INT_MAX - 1) {
} else {
return 0;
}
} else {
if (x > INT_MIN + 1) {
} else {
return 0;
}
}
if (x < 0) {
negative = 1;
x = -x;
}
char str[1000];
sprintf(str, "%d", x);
len = strlen(str);
if (x < 0) {
negative = 1;
x = -x;
}
for (int i = 0; i < len / 2; i++) {
tmp = str[len - 1 - i];
str[len - 1 - i] = str[i];
str[i] = tmp;
}
long long ans = strtol(str, (char **)NULL, 10);
if (ans) {
if (ans < INT_MAX - 1) {
} else {
return 0;
}
} else {
if (ans > INT_MIN + 1) {
} else {
return 0;
}
}
if (negative == 1)
ans = -ans;
return (int)ans;
}
int main() {
printf("%d --> %d\n", 123, reverse(123));
printf("%d --> %d\n", -123, reverse(-123));
printf("%d --> %d\n", 120, reverse(120));
}
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