#include<iostream>
#include<algorithm>
using namespace std;
int main(){
    int n,h[100005],ans=0,amx=0;
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>h[i];
        amx=max(h[i],amx);
    }
    for(int i=1;i<=amx;i++){
        bool flaged=1;
        for(int o=1;o<=n;o++){
            if(h[o]>=i){
                if(flaged){
                    ans++;
                    flaged=0;
                }
            }else{
                flaged=1;
            }
        }
    }
    cout<<ans<<endl;
}

洛谷评测机#9 1.03s

本地使用Competitive Programming Helper + VSCode测试结果为 805ms

编译器版本 (g++ -v):

Using built-in specs.
COLLECT_GCC=C:\mingw64\bin\g++.exe
COLLECT_LTO_WRAPPER=C:/mingw64/bin/../libexec/gcc/x86_64-w64-mingw32/12.1.0/lto-wrapper.exe
Target: x86_64-w64-mingw32
Configured with: ../../../src/gcc-12.1.0/configure --host=x86_64-w64-mingw32 --build=x86_64-w64-mingw32 --target=x86_64-w64-mingw32 --prefix=/mingw64 --with-sysroot=/c/buildroot/x86_64-1210-win32-seh-rt_v10-rev3/mingw64 --enable-host-shared --disable-multilib --enable-languages=c,c++,fortran,lto --enable-libstdcxx-time=yes --enable-threads=win32 --enable-libgomp --enable-libatomic --enable-lto --enable-graphite --enable-checking=release --enable-fully-dynamic-string --enable-version-specific-runtime-libs --enable-libstdcxx-filesystem-ts=yes --disable-libstdcxx-pch --disable-libstdcxx-debug --enable-bootstrap --disable-rpath --disable-win32-registry --disable-nls --disable-werror --disable-symvers --with-gnu-as --with-gnu-ld --with-arch=nocona --with-tune=core2 --with-libiconv --with-system-zlib --with-gmp=/c/buildroot/prerequisites/x86_64-w64-mingw32-static --with-mpfr=/c/buildroot/prerequisites/x86_64-w64-mingw32-static --with-mpc=/c/buildroot/prerequisites/x86_64-w64-mingw32-static --with-isl=/c/buildroot/prerequisites/x86_64-w64-mingw32-static --with-pkgversion='x86_64-win32-seh-rev3, Built by MinGW-W64 project' --with-bugurl=https://sourceforge.net/projects/mingw-w64 CFLAGS='-O2 -pipe -fno-ident -I/c/buildroot/x86_64-1210-win32-seh-rt_v10-rev3/mingw64/opt/include -I/c/buildroot/prerequisites/x86_64-zlib-static/include -I/c/buildroot/prerequisites/x86_64-w64-mingw32-static/include' CXXFLAGS='-O2 -pipe -fno-ident -I/c/buildroot/x86_64-1210-win32-seh-rt_v10-rev3/mingw64/opt/include -I/c/buildroot/prerequisites/x86_64-zlib-static/include -I/c/buildroot/prerequisites/x86_64-w64-mingw32-static/include' CPPFLAGS=' -I/c/buildroot/x86_64-1210-win32-seh-rt_v10-rev3/mingw64/opt/include -I/c/buildroot/prerequisites/x86_64-zlib-static/include -I/c/buildroot/prerequisites/x86_64-w64-mingw32-static/include' LDFLAGS='-pipe -fno-ident -L/c/buildroot/x86_64-1210-win32-seh-rt_v10-rev3/mingw64/opt/lib -L/c/buildroot/prerequisites/x86_64-zlib-static/lib -L/c/buildroot/prerequisites/x86_64-w64-mingw32-static/lib ' LD_FOR_TARGET=/c/buildroot/x86_64-1210-win32-seh-rt_v10-rev3/mingw64/bin/ld.exe --with-boot-ldflags=' -Wl,--disable-dynamicbase -static-libstdc++ -static-libgcc'
Thread model: win32
Supported LTO compression algorithms: zlib
gcc version 12.1.0 (x86_64-win32-seh-rev3, Built by MinGW-W64 project)