代码放这了 你们直接抄就行

#include <unistd.h>

static char inBuf[1 << 10];
static int inLen = 0, inPos = 0;

inline int readChar() {
if (inPos == inLen) {
inLen = read(0, inBuf, sizeof(inBuf));
inPos = 0;
if (inLen <= 0) return -1;
}
return inBuf[inPos++];
}

inline int readInt() {
int c = readChar();
while (c <= ' ') { if (c == -1) return -1; c = readChar(); }
int x = 0;
while (c > ' ') {
x = x * 10 + (c - '0');
c = readChar();
}
return x;
}

int main() {
int a[105];
int n = 0;
int v;
while ((v = readInt()) != -1) {
a[n++] = v;
}
int y = a[--n];
int x = a[--n];
int ans = a[x - 1] + a[y - 1];

char out[16];
int len = 0;
if (ans == 0) out[len++] = '0';
else {
    if (ans < 0) { out[len++] = '-'; ans = -ans; }
    char tmp[12]; int tl = 0;
    while (ans) { tmp[tl++] = '0' + ans % 10; ans /= 10; }
    while (tl) out[len++] = tmp[--tl];
}
out[len++] = '\n';
write(1, out, len);
return 0;

}